tutorial: managing geoattributes · the first exercises in ... tntmips pro, tntmips basic, and...

ManagingGeoattributes

Tutorial

TNTedit™TNTview®

with

TNTmips®

MANAGING

ATTRIB

Managing Geoattributes

Before Getting StartedTNTmips®, TNTedit™, and TNTview® provide a complete set of tools for asso-ciating attributes with geospatial objects and maintaining these attributes as youextract, merge, edit and otherwise manipulate these objects. You can view thecomplete set of associated attributes, attributes associated with selected elements,or use attributes of interest to select elements.

Prerequisite Skills This booklet assumes you have completed the exercises inthe Displaying Geospatial Data and TNT Product Concepts tutorial booklets.Those exercises introduce essential skills and basic techniques that are not cov-ered again here. Please consult these booklets for any review you need.

Sample Data The exercises presented in this booklet use sample data distrib-uted with the TNT products. If you do not have access to a TNT products DVD,you can download the data from MicroImages’ web site. The first exercises inthis booklet use the CBUTTE Project File in the ATTMGT directory of DATA. Theobjects in the other Project Files in this directory are also used. Make a read-write copy of the sample data on your hard drive so changes can be saved whenyou use these objects.

More Documentation This booklet is intended only as an introduction to theattribute management techniques in TNTmips, TNTedit, and TNTview. There isa companion booklet, Managing Relational Databases, that discusses generaldatabase management issues, such as importing or linking to external databases,creating new tables and forms, and establishing relationships between tables.You may also wish to consult the TNTmips reference manual for additionalinformation.

TNTmips Pro, TNTmips Basic, and TNTmips Free TNTmips comes in threeversions: TNTmips Pro, TNTmips Basic, and TNTmips Free. HyperIndex Linkeris available only to customers using TNTmips Pro. If you did not purchase theprofessional version (which requires a software license key), you are usingTNTmips Free or TNTmips Basic, which limit the size of your project materials.All exercises in this booklet can be completed in TNTmips Free using the samplegeodata provided.

It may be difficult to identify the important points in some illustrations without acolor copy of this booklet. You can print or read this booklet in color fromMicroImages’ web site. The web site is also your source of the newest tutorialbooklets on other topics. You can download an installation guide, sampledata, and the latest edition of the TNT products.

http://www.microimages.com

Merri P. Skrdla, Ph.D., 1 October 2009© MicroImages, Inc. 2001–2009


Welcome to Managing GeoattributesTwo major features separate GIS software packagesfrom simple graphics packages: use of georeferenceinformation and attribute management. These top-ics are so important to the overall understanding ofthe potential applications of the TNT products thatthey are presented in companion sets of booklets.The Introduction to Map Projections andGeoreferencing tutorial booklets present the formertopic while this booklet and the Managing Rela-tional Databases tutorial booklet address the latter.

This booklet describes many facets of attribute man-agement, such as attaching attributes to elements ingeospatial objects, using attached attributes to se-lect elements, viewing attributes attached to ele-ments, and viewing geotagged photos and theirlocations. The implications of various attribute at-tachment types for ease in manipulation both whencreating attachments and when combining or edit-ing objects are also described. Although many ofthe same topics are discussed in this booklet and itscompanion, the approach is different. In this book-let, for example, the Database Editor functions areapproached as a means of familiarizing you withthe structure of a database that is associated withelements in a geospatial object. The Managing Re-lational Databases booklet approaches the func-tions of the Database Editor mechanically,addressing what the right and left mouse buttons doin each of the editing modes.

You should probably start your journey to under-standing relational databases and attribute manage-ment with the Managing Relational Databasesbooklet because creating tables is handled at lengththere. This booklet assumes you have a basic un-derstanding of this topic and database terminology.

An important use of attributes not covered in thisbooklet is the generation of GeoFormula layers fromattached attributes. This topic is presented in theUsing Geospatial Formulas tutorial booklet.

STEPS

launch TNT

copy the files in theATTMGT data collection toyour local drive

The exercises on pages 4and 5 familiarize you withdatabase structure as pre-sented in the Database Edi-tor. Viewing attributes isdescribed on pages 6–7 andagain on 18 with the fea-tures of single record andtabular views discussed onpages 8–16. Systemtables, raster attributes,attaching attributes, viewingattributes as DataTips, anddetermining whether at-tributes are attached isdiscussed on pages 16–28.The implications of variousattachment types, transfor-mation of computed fields topermanent fields, and meth-ods of attaching records inthe TNT’s Editor are alsodiscussed. The bookletconcludes with exerciseson XY Plots, CAD snap-shots, using .dbf files, andgeotagging digital photos.


Database StructureSTEPS

choose Tools/Database/Edit from the TNT menumenu and selectCBSOILS_LITE from theCBUTTE Project File

click on the Polygonradio button in theSelect window, thenon [OK]

right-click on the linkbetween the CLASS andMAPUNIT tables andchoose Show Link fromthe popup menu

note that the musymfield of the MAPUNIT tableis related to the Classfield of the CLASS table,then click on [Close]

right-click on the linkbetween the POTENTIAL

and CLASS tables andchoose Show Link

through what twofields are thesetables related?

do key fields usedto relate tableshave to have thesame names?

click on [Close] inthe Relate window

The purpose of this exercise is to get you to thinkof the Database Editor as a tool to acquaint your-self with the structure of a database so you can evalu-ate the most logical relationships to set up for

additional tables. Creating direct attach-ments to elements can be a lot of work andis unnecessary if you use the relational da-tabase features of TNTmips to establish in-direct relationships using the information

in fields in other tables.

The Crow Butte soil map polygon database con-tains many tables (24*), which provide a good il-lustration for the utility of a graphical DatabaseEditor. The features of the Database Editor that letyou make changes in the database structure are de-scribed in the Managing Relational Databases tu-torial booklet.

The records intables shown linkedto the internal ele-ments table are di-rectly related(attached) to theelements.

Records in tablesshown linked throughother tables are indir-ectly related to theelements they de-scribe.

* Note that the internal table is not actually a table,but is a construct to store internal information aboutthe elements. See more in the laterexercise on system tables.


STEPS

right-click on the box forthe POTENTIAL table andchoose Properties fromthe popup menu

Relationships in Table PropertiesHopefully, the answer to the second question on thepreceding page was obvious; the same names arenot required for the fields in a primary key / foreignkey relationship. You can even change the field

confirm youranswer to thefirst questionin the previousexercise(Field panel)

highlight afield otherthan theSYMBOL field inthe list at theleft of thewindow and

note that the Relate tokey option menu is setto None

click and hold the Relateto key option button toview all the primary keysdesignated in the tablesof the polygon database

click [Cancel] in thedefinition window, thenchoose Close from theFile menu in theDatabase Editor window

names after estab-lishing the rela-tionship without aproblem.

The entries on theRelate to key op-tion menu are allthe primary keyscurrently desig-nated for tables inthe database (inthe form Table.Field). The entries in the primary /foreign key fields of related tables must match ex-actly for indirectly related records and elements tobe identified. For example, if the information in theprimary key field is soil type, it cannot be just thesymbol in one table and the symbol followed by thedescription in the other. If state name is the primarykey field, the entries cannot be in upper and lowercase in one table and all capitals in the other.

These fields relate thePOTENTIAL and CLASS tablesto one another.

When the Attachment Type is set to Re-lated Only, selecting elements identifiesrecords with the same attribute valuesas records selected in the table with thechosen primary key. Attachment typesare explored further in later exercises.


Attributes in View Window LegendSTEPS

choose Display from theMain menu,open a new2D group,and selectCBSOILS_LITE

from the CBUTTE ProjectFile in the ATTMGT folder(keep this object openfor the next exercise,but you may want tolook at additionalLegendViews byopening other groups)

When the Show Legend option is turned on in theView window, you get an automatic legend for eachlayer that shows the style assigned to elements se-lected for drawing (vector, shape, CAD, TIN). Avariety of automatic legend types are available forraster layers (area sample, image thumbnail, con-tinuous color scale, color scale ranges, color sample,and theme map ranges). The legend display can beturned off for individual layers or for all layers.

The order of layers can be rearranged by drag-and-drop in both the View window’s legend and the Dis-play Manager. You will probably want to hide thelegends for layers with many attribute values be-fore using this feature.

Layers may have so manyattribute values that you needto scroll to view them all inLegend View, as with the soilmap shown at right. Note alsothat lines are shown in theassigned drawing style (AllSame). In the vector belowonly lines are selected fordrawing and there are only fiveattribute values. You canchange the legend label to bethe text from any related field.

The LegendView at the right shows a colorscale legend for a color mapped elevationraster and the styles for contours gener-ated directly from TIN elements.


Viewing Objects and AttributesSTEPS

starting with CBSOILS_LITE

added in the lastexercise, expand thelayer and the polygondatabase in the DisplayManager

turn on the Show Tablecheck boxes for theCLASS and POTENTIAL

tables

right-clickon thepolygondatabase level andchoose Mark By Query

click on the Openicon, choose OpenRVC Object, and selectthe SELECT4 object in theCBUTTE Project File

click on [Apply] and viewattributes for markedelements

The Select tool must be active to select elements withthe mouse, but elements can be selected by querywhen any of the tools are active. When selectingmultiple elements, you probably want to view data-base records in tabular view so that you can see theinformation for all selected elements. Single recordview only has knowledge of the active element whenretrieving related records.

Tabular view has three viewing modes: Show Ac-tive Element Records, Show Marked ElementRecords, and Show All Records. Show Active Ele-ment Records is most useful when you are selectingsingle elements with more than one record attached.Show Marked Element Records is best suited forviewing attributes when you are selecting multipleelements with a single record attached. The ShowAll Records mode is most useful for viewing at-tributes without regard for which elements are at-tached or when using records to select elements.

View records formarked elements.

Primary key field

Continue directly to the next exercise withCBSOILS_LITE displayed and these polygons selected.

Foreignkey field

The length of the scroll bar tells you that onlyabout half of the fields are currently visible.


STEPS

choose Switch to singlerecord view from theTable menu in thePOTENTIAL table or click onthe corresponding iconon the tabular viewtoolbar

right-click on the polygondatabase row andchoose Next Marked

continue selecting NextMarked until you havestepped through therecords attached to thefour selected elements

click on the Show Tablecheckbox for thePOLYSTATS (standardpolygon attributes) table

change to single recordview, click on the unitsfield and alter the unitsshown for some of thefields, and observe thedifferences

Single Record View of Database TableYou can view tables a single record at a time or withmultiple records in a tabular presentation. Thereare features unique to each viewing mode. The useof picklists for attribute assignment is available fromsingle record view only. Picklists and tabular viewsare discussed in later exercises.

Single record views may be more convenient forviewing or entering attribute values for individualelements in tables with a large number of fields.The number of records attached to the active ele-ment is immediately apparent in single record view,as are the current units for individual fields. Youcan step through the records related to a set ofmarked elements in single record view using thePrevious and Next Marked selections from thedatabase’s right mouse button menu to change thecurrently active element.

The number of records related to the ac-tive element, the record number, and thetotal number of records in this table areshown here.

You can change the unitsused for viewing fields to anyof those available for the des-ignated type of unit (e.g.,area, distance, angle, time,

temperature, vol-ume). Whether afield has units, thetype of unit, and theunits in which exist-ing field values wereoriginally enteredare all designated inthe table properties.

The active element is relatedto this record when this but-ton is on.Use thisbutton toattach therecord tothe activeelement(except inrelatedonlytables).

Use this icon to switch to tabular view.

Step through the records in the tablewhether or not they are related to theactive element using these icons.

Step through records related to theactive element using these icons.

Each row in single record view presentsa field name, its value, and units if set.


Show active element recordsShow marked element records

Show all records

Tabular View of Database TableA number of selection and viewing features areavailable only from a tabular view window, such assorting, statistics and substatistics, X-Y plots of se-lected fields, element selection from attributes, andsimultaneous viewing of attribute information formultiple selected elements.

You can change the type of units used for display intabular view by choosing Options from the Fieldmenu for the selected field or Field Options fromthe Right Mouse Button Menu (RMBM) for thefield name. However, the unit type isn’t shown be-cause of the tabular structure, and it takes three clicksrather than the two clicks needed in single recordview to change the unit type. A left-click on a fieldname (column heading) in tabular view selects thatfield for Field menu actions.

Tabular view reports the totalnumber of records related toall marked elements.

STEPS

choose Switch to tabularview from the Tablemenu in the POTENTIAL

table or click on thecorresponding iconon the toolbar

rotate through the threeviewing modes in thePOTENTIAL table for theelements selected on p.7

right-click on the Areaheading in the tabularview of the POLYSTATS table

change the units tosquare kilometers andreduce the number ofdecimal places if desired

click OK and view theresults

In the Show active element recordsmode, more than one record will beshown if the active element hasmultiple records attached. In theShow marked element recordsmode, all records related to allmarked elements are shown.

Records attached to the ac-tive element are highlighted ina different color than the oth-ers in the selected set. In theShow all records mode, thehighlighted records in the se-lected set are interspersedwith the records that are notrelated to selected elements.

RMBM for the columnheading (field name)

only active for virtual fields

field selected

not selected


Single Record vs Tabular View MenusYou should have noticed that field names run acrossthe top of the table in tabular view and down theleft side of the table in single record view. Anothermeans of identifying the current viewing mode isthe icon to switch between modes. The differentfeatures in single record and tabular view also re-sult in different menu choices. Also, only tabularview has a Field menu.

When fields are edited in either table viewing mode,the default behavior is to automatically save thosechanges. You can turn on prompting before saving(i.e., before switching to another record) on the Table

menu in single record view.Changes made in tabularview are always saved whena save initiating event oc-curs, such as closing thetable or selecting elements.Saving can also be initiatedin either view by clickingon the Save icon. Standardstatistics and system tablesare not editable.

STEPS

you should have thePOTENTIAL table open intabular view and thePOLYSTATS table in singlerecord view from theprevious exercises

compare the menus ineach of the two views

turn Row controls andShow status line togglesoff on Table menu forPOTENTIAL table and notethe effects, then turnboth back on

Choices areHide, Top, orBottom (onField menu intabular view).

single record viewtabular view

Deletes high-lighted entry.

Inserts contentsof selected fileafter cursor upto designatedfield width.

Use to insertglyphs that cannotbe typed directly.

These functions are alsoavailable from icon but-tons on the single recordview toolbar.

Choices are XYPlot and Histo-gram (see laterexercises).

You can also open this windowby right clicking on afield heading. Thesesettings are forviewing only and donot affect the tableproperties.

Restrict who canview or modify thetable if you havethis option en-abled in TNT.

Apply to recordsselected by rowcontrols.


STEPS

close the POLYSTATS andPOTENTIAL tables

click on the Geo-Toolbox icon (Viewwindow) then theSelect icon (Geo-Toolbox window)

click on the upper leftpolygon

open the PLANTCOM table

switch between viewingactive and selectedelement records and noteany differ-ences inrecords shown

click on the Rec-tangle selection tool,outline asmall area inthe upper leftas shown, andclick [Select Elements]

switch between viewingactive, selected, and allrecords noting thedifferences in thenumbers of recordsshown

Selecting Elements to View AttributesThe selected set for the exercises beginning on page7 was determined by query. Selecting elements withthe mouse or by region requires that the elementtype be enabled for marking (elementrow in the Display Manager) and thatthe Select tool in the View window or theGeoToolbox is active.

The tool used to select elements is chosen in theGeoToolbox window while the mode in which thetool operates is set on the Group or Layout Controlswindow. The single Select tool is found in both theView and GeoToolbox windows. In Exclusive se-lection mode, which is the default, each new selec-tion action deselects the previously selectedelement(s). A single selection action selects one (ormore) of each element type that has the Select iconturned on in its table / selection icon row.

You see the same records withView Active or Selected ElementRecords chosen with only oneelement selected.

The size of the scroll bargives you an idea of the pro-portion of records to beviewed currently shown.

Note that all other panels inthe GeoToolbox are avail-able when a tool other thanSelect is chosen.

Polygons but not linesavailable for selection.

disabledenabled


Using Attributes to Select ElementsPerhaps you are looking for an area suitable forwetlands as part of an exchange for wetland acresyou want to use for farming on nearby property.The Crow Butte area has only one soil type remotelysuitable for wetlands and wetlands wildlife. If therewere multiple soil types, you would simply click ineach corresponding checkbox for the records to useto identify related polygons.

You need to turn on View All Records unless theelements you want selected are a subset of thosealready selected. There are four methods you canuse to select elements once the attributes for selec-tion are identified: Exclusive (deselects previouslyselected before selecting related elements), Select

Elements (add tocurrent selectedset), Deselect Ele-ments (removefrom selected set),Toggle elements(select if not cur-rently selected,deselect if in se-lected set).

A series of recordscan be selected by clicking on the first(or last) then holding down the shiftkey and clicking on the Select Recordbox at the other end of the series. Se-lecting multiple consecutive records

can be mixed with selecting individual records inthe table by making single click and click / shift-click combinations.

STEPS

close the PLANTCOM tableand open the POTENTIAL

table in tabular view

click on the View AllRecords icon

click in the Select Recordbox (tabular view) of therecord with Bd as theSymbol value

click on the Exclusiveicon in the POTENTIAL

table

note the polygons selec-ted in the View windowand the number of ele-ments selected reportedin the polygon row of theManager window

The number of polygonscurrently selected and thetotal number of polygonsare shown here.

click

click

shift-click

click

You can quickly choose the desired records for se-lecting elements using a combination of clicks andshift-clicks. The row controls (Table menu) must beon for you to use this selection method.


Table Viewing PreferencesSTEPS

in the POTENTIAL table,choose Preferences fromthe Table menu

turn off the 3D toggle,click [OK] and note thedifference in appearance

drag the vertical scrollbarslider (POTENTIAL); watchthe DataTip change

return to the Preferen-ces window, change theVertical Scrollbar Tipoption menu to RecordNumber, turn off AutoScroll to First MarkedRecord, and click [OK],then scroll through thetable again

click on the Selecticon in the Viewwindow, turn on theShow All Recordsicon in the POTENTIAL

tabular view

select a series ofpolygons; note therecord attached to theselected element is onlyapparent if it is alreadyshown in the tabularview

return to the Preferen-ces window, turn on AutoScroll to First MarkedRecord, set the ScrollbarTip back to Sorted FieldValue, and click [OK]

select a series ofpolygons and note howthe table scrolls

You can change a number of settings that affect theappearance of your tabular view. The default set-tings are initially applied to all tabular views. Thechanges you make are saved with the individualtables. The first group oftoggle buttons lets youchoose whether or not to drawgrid lines between field andrecord values and how thelines appear if drawn. Turn-ing off the 3D effect for gridlines saves one pixel per rowor column, and turning off theline altogether reduces theheight or width by one more pixel. If your monitorspace is limited, such as on a portable, this spacesavings may outweigh having cells clearly divided.The color interleave capability can compensate forlack of row separation by grid lines.

The Realtime Scrolling option lets you see recordsfly by as you drag the scroll bar (or click and holdin the trough). The tabular view is not updated untilyou release the scrollbar when the option is turnedoff. There is no difference between on and off whenyou scroll using the up and down arrows. You canchoose to have a Scrollbar Tip, which reports thedesignated value for the current top row in the tabu-lar view while scrolling. The choices for theScrollbar Tip are the value of the sorted field, therecord number, the row number, or none.

3D horizontal and vertical 3D off, horizontal only 3D off, vertical only

The same area of a tabular view was captured for thethree illustrations below. Note how the fifth entry isbarely visible with 3D grid lines, mostly visible with 2Dlines, and fully shown with horizontal lines off.


STEPS

with the POTENTIAL tablestill open, pause thecursor over the dividerbetween the GRAINS andLEGUMES columns, clickthe mouse when thecursor is the doublearrow and pull the dividerleft (example showseven more unused area)

open the YIELD

table, click on the HAYDRY

column heading, andchoose Optionsfrom the Field menu

add a comma and aspace between HAY

and DRY in the Labelfield, and change thenumber of decimalplaces to 0, thenclick [OK]

note the new columnheading and that the dryhay yields have beenrounded rather thantruncated

open the Field Optionswindow for the SYMBOL

field, change the name toClass, and click [OK]

Field OptionsYou set the width of each field in the Table Defini-tion window, but you can choose a different widthfor display in tabular view. You change columnwidth in tabular view by dragging the divider be-tween columns. (This divider remains when youturn off vertical grid lines.) The cursor becomes adouble-headed arrow when over the divider andactive for changing column width. If you clickwhen the cursor is the left arrow shape instead, you

select the column heading and activate addi-tional choices on the Field menu.

There are three ways to get at the Field Op-tions window: left click on the columnheading and choose Options from theField menu or right-click on a columnheading or over a cell in the table andchoose Field Options from the popupmenu. The Label field lets you changethe column heading from the field name

assigned in the table properties. This label is notrestricted to 15 charactersand may contain spaces.The Decimal Places fieldonly appears in the windowif a numeric field is se-

lected. Changing the setting in the Decimal Placesfield changes the number of places shown withoutchanging the number calculated, which is set in theTable Properties window. You can set the numberof decimal places for integer fields because theymay have units assigned and unit conversion cancreate non-integer values.

After three changes,the YIELD table ap-pears as at the right.


Right Mouse Button MenusSTEPS

click on the Selecticon in the Viewwindow, then click onany polygon

right-click over any ofthe fields (except theStyle field) in the POTENTIAL

table for CBSOILS_LITE

polygons; why are thechoices concerned withattaching andunattaching recordsdimmed?*

right-click on the Classfield in a record showingvalues in the CLASS table;note that all menuchoices except MakeField Permanent areactive

click on the Unmark Allicon in the Viewwindow

repeat step 3 showing allrecords, and note thechoices that are nolonger active

right-click on the headingof the Style column, notethe inactive entries onthe menu, then right-click on the Classheading and note thesame

right-click on the SelectRecord button of arecord with valuesshowing

right-click on the layername (Display Manager)and choose RemoveLayer

* The attachment type for the PO-TENTIAL table is Related Only;records are indirectly related toelements through the Symbol fieldand, thus, cannot be attached orunattached.

Many of the functions available from the Recordand Field menus are also available from right mousebutton popup menus over atabular view. If you rightclick over an individual cellin a tabular view, you get allthe Record menu choices,except New, and all Fieldmenu choices that deal withthe field you click on (notPlot, Show All, or Show Style Sample).You get only Field menu choices ifyou right-click on a column headingand only the Record menu options if you right-clickover a Select Record checkbox. These right mousebutton menus are provided as a convenience to re-duce the number of clicksneeded to accomplish a task.(The click on the columnheading or record selectioncheckbox required before se-lecting from the Field orRecord menu, respectively, iseliminated.)

Choices on the popup menu may be dimmed be-cause they are inappropriate for the selected field(Make Field Permanent is dimmed for all but com-puted fields) or record (see Step 2). The attach andunattach options are also dimmed if no elements areselected. If the tabular view window issized or viewing options are set such thatblank lines appear in the table, only thefield menu options are active in the blank portionof the table.


Sorting by One or More FieldsSTEPS

add theWESTERNUS

vector objectin the STATES

Project Fileand open theCITIES table inthe pointdatabase

right click onthe CITYCODE

heading and chooseHide Column

scroll untilthe POP fieldbecomesvisible, left-click andhold on the columnheading, then drag theheading outline to the left;release the mouse whenthe box is between theSTNAME and DIVNAME fields

click on theSTNAME heading,press and holdthe <shift> keyand click on theCITYNAME heading

choose Sortfrom the Fieldmenu

notice thenew order ofrecords

repeat step 4

choose Sort from theField menu again, andnote the result

you will probably want tosort on these two fieldsone more time unlessyou are comfortableworking in reversealphabetical order

Before actually sortingfields in this exercise,let’s rearrange the table tomake the sorted resultsmore easily viewable(and demonstrate morefeatures of tabular view).Sorting lets you putrecords in a new order forviewing in either numericor alphabetical order.The first time you sort on

a field, its val-ues are placedin ascendingorder (smallest

first). If a field has been sorted in ascending orderand you elect to sort it again, it appears in descend-ing order.

Sorting on more than one field lets you introduceadditional organization in your tabular views. The

order in which you se-lect the fields is impor-tant. The first fieldselected needs to havemultiple records withthe same value, such asin this example wherethere are many recordsfor each state. If youselect the city name

field first, each record is unique (because the stateabbreviation is also included), so no further sortingwould occur for any other selected fields. In thewestern states example, you could take the sortingone step further by selecting the division name field(DIVNAME) first, then state, then city. All of the citiesin all of the states in the mountain division wouldthen be listed before any of the states in the Pacificdivision (Wyoming would come before California).

click at the right, dragand drop at the left


System TablesNot all tables are shown automatically when youexpand the database level in the Display Manager.There is a type of table referred to as system tablesthat is not shown unless you choose the Show Sys-tem Tables option on the right mouse button menu(RMBM) at the database level. The system tablesinitially hidden contain information not generallyof interest to the user. You may, however, at somepoint want to know the number of vertices in a se-lected line or the coordinates of a point, and youcan get this information from the system tables.

The system tables revealed when you choose ShowSystem Tables are of three types: the internal table,style assignment tables, and S-57 picklist tables*.The first two types are represented with a differenticon than used for user-defined tables. All objecttypes except CAD objects have an internal table,which is not actually a database table but a tabularpresentation of the information for each of the ele-ments in an object. The internal table uses elementnumbers to reference each element and CAD ob-jects do not have element numbers. You can getsimilar information for an active CAD element bychoosing Internal Element Details from the RMBMat the object level in the Display Manager. Thischoice is available for all object types except ras-ters. You can step through the information for ele-ments in a selected set using the Previous Markedand Next Marked buttons in the View window.

STEPS

with the group from theprevious exercise open,right-click on the polygondatabase line in theDisplay Manager andselect Show SystemTables

open the Internal tableand switch to singlerecord view

right-click on the polygondatabase line again andchoose Mark All

note the informationprovided

right-click on the objectname in the DisplayManager and chooseInternal Element Details

compare the informationshown with that in theinternal table

click on the NextMarked icon in theView window

note that both the tableand the internal elementinformation are updated

* S-57 picklist tables are pre-defined, editable tables. Theyare placed with the systemtables because they are sonumerous.


Raster AttributesA variety of methods are available for viewing ras-ter attributes, which may simply be the cell valueor may be the results of a classification or statisti-cal process. Attributes associated with raster cellscan be viewed as DataTips, in the view’s legend, orin database form using the selection tools in a man-ner similar to viewing geometric object attributes.

The classification processes automatically create atable that lists the classes identified by the process(with either their default numeric name or an al-tered name you provided). You can calculate sta-tistics for these classes based on some other raster’svalues, such as a yield map or elevation raster.

STEPS

open a New 2DDisplay and selectCLS_MAXLIKE from theCROPMAP Project File; notehow the attributes aredisplayed in LegendView

open the CLASS table,click on the Selecticon (View window), thenclick on different areas inthe image and view theassociated attributes

choose Raster/Interpret/Statistics by CategoryRaster from the TNTmenu

click on [Select] andselect DEM_16BIT from theRASTPROP Project File

click on [CategoryRaster] and chooseCATEGORY from the sameProject File

click on [Run] andaccept the defaultdatabase table name

open a new 2DDisplay in theDisplay processand choose both rastersin the RASTPROP ProjectFile (DEM_16BIT first)

click on the Selecticon in the Viewwindow

open the DEM_16BIT tableunder the CATEGORY raster,then click anywhere overthe Category raster,change to single recordview if not shown thatway, then click on thecategory areas to viewthe statistics

Nebraska NationalForest

Ponderosa StateWildlife Area

This record provides theminimum and maximum el-evation in the PonderosaState Wildlife Area, as wellas other statistical informa-tion about elevation in thisarea.


Raster Attributes from External FilesSTEPS

choose Import from theMain menu, then click on[Select Files] and selectFRAGSTAT.DBF from theATTMGT folder

select thedatabase dbfoption, then click [Next]

accept the defaults andclick [Import]

navigate to the RASTDBASE

under the ALASKA rasterin the RASTERDB ProjectFile, click [OK], thenclick on the NewObject icon andaccept the default name

open a New 2DDisplay, and selectALASKA from the RASTERDB

Project File

show details forthe layer, then right-clickon the fragstat table andchoose Properties

for the Type field set theRelate to Key option toInternal.Value, then click[OK]

open the FRAGSTAT tableand switch to singlerecord view

choose the Selecttool and click on thevarious colors in theraster to view theassociated FRAGSTATS

information for eachclass

Some TNTmips processes create database tables as-sociated with the raster’s cell values. You may haveother database information you would like to asso-ciate with the raster, such as the FRAGSTATS class sta-tistics used in this exercise.

FRAGSTATS is used by landscape ecologists and otherscientists to quantify landscape structure for thepurpose of studying function and change. The ba-sic unit for these fragmentation statistics is the patch,which is a piece of the area of interest, or landscape,that is considered homogeneous at the scale of aparticular study. Patch type is equivalent to a class.You can run FRAGSTATS in TNTmips using one of theSML scripts provided with TNT. One of these scriptsis a tool script and one runs in the main scriptingprocess (Script/Run or Script/Edit Script).

The only means of associating database informa-tion with rasters is by cell value. So although youcould import the more detailed individual patchinformation calculated by the fragstats script, allthe records having the same patch type would beassociated with anycell of that patch type.For more informationabout fragstats seew w w. u m a s s . e d u /l a n d e c o / r e s e a r c h /fragstats/documents/fragstats_documents.html.


Viewing Attributes by DataTip

Selecting a memo fieldfor DataTips can pro-vide much specificinformation when youpause the cursor overelements of interest.

DataTips are similar to the ToolTips that appearwhen you pause over an icon except you controlwhat information is presented on a layer by layerand element by element basis. DataTips present thevalue from a selected database field for the elementor cell nearest the cursor when paused. You canspecify the DataTips you want in the Layer Con-trols or from the Setup DataTips option on theRMBM for each layer. When you use the SetupDataTips option, you can also set the delay timebefore a DataTip appears and the number of pixelsthat the cursor must move before a DataTip will beupdated.

You control whether DataTips are turned off orwhether you see them for all layers or only the ac-tive layer using the DataTips cascade on the Optionsmenu in the View window. You can have one Data-Tip for each raster, CAD, shape, and database pinmaplayer. You can have one DataTip for each elementtype in vector and TIN layers.

STEPS

open a new 2Dgroup in theDisplay process andchoose 16BIT_RGB andCBSOILS_LITE from theCBUTTE Project File

right-click on the CBSOILS_LITE layer and chooseSetup DataTips from thedrop down menu

on the Lines panel checkthat LINESTATS. Lengthis selected (click on[Field] and select it if it’snot)

on the Polygons panelcheck that POLYSTATS.Area is selected

click on the LayerControls icon for theraster layer, click on theDataTip tab and set theShow option to ImageCell Value

choose Options /DataTips / All Layers inthe View window

move your cursor tovarious positions in theView window, pause, andnote the DataTips thatappear

DataTips are turned on for lines and polygons in thevector layer and for cell values in the raster layer (aboveleft). The vector layer was selected a second time (hid-den, above right) to give two different polygon attributesin the DataTip. (The line DataTip is off.) You can alsocreate multiline DataTips with a string expression fieldwithout adding an object multiple times.

You can enter any text youwant in the Prefix and Suffix fields.

If you toggle onthis button, theelement is high-lighted when itsDataTip is shown.You can turn offpolygon fillingwhen highlightedon the Polygonpanel of the LayerControls.


DataTip Viewing Modes

STEPS

with the same groupused in the lastexercise, chooseOptions/DataTips/LayerName, and hover themouse over the upperleft of the raster

move the mouse to thelower right and pauseagain

change the DataTipviewing mode to Active/Top Layer and againpause your mouse atthe upper left and lowerright of the image

The TNT products provide six differentDataTip viewing modes: None, Active/TopLayer, Visible Layers, Maximum, Auto-matic by Scale, and Object Names. TheActive/Top Layer option displays theDataTip for the active layer or for the toplayer if no layer in the group you are hov-ering over is the active layer. The VisibleLayers option includes information only for thoselayers currently in the View, which excludes layersthat are off by map scale as well as those that arehidden. The Maximum option shows DataTips forall layers with elements near the cursor location butis limited to a maximum of 20 lines (or a few more ifthe 20th line begins a multi-line DataTip). ThatDataTips for all layers are not shown is indicatedby putting an ellipsis (...) at the bottom of the list.The Automatic by Scale option applies to layersthat are turned on/off by map scale. Layer informa-tion will appear in the DataTip with this option un-til you are zoomed in 100X more than the map scaleat which the layer stops displaying or zoomed out10X more than the scale at which the layer startsdisplaying. Thus, a layer that is set to display be-tween 1:1,000,000 and 1:240,000 will appear in theDataTip at viewing scales between 1:10,000,000and 1:2,400. The Object Names option providesmore than the object name as illustrated after step 1.

Depending on the data you have displayed, differ-ent DataTip options may produce the same result.For example, when theactive layer has noDataTip set up and mostlayers are off by mapscale, None, Active/TopLayer, and Visible Lay-ers may give the sameresult.

Automatic by ScaleMaximum

Two different DataTip view-ing modes for the sameapproximate location canproduce considerably dif-ferent results.


Multiline DataTipsYou may want to view the information from a num-ber of different fields for a single layer. You couldadd the layer multiple times and specify a differentfield for the DataTip in each layer. But this is te-dious and potentially confusing if the informationis to be used by anyone else, such as in a publishedatlas. You can get DataTips from multiple fields in

the same table by adding a string ex-pression field that specifies the fieldsto include.

This expression needs to include the label you wantfor each value (in quotes), identification of the cor-responding field (converted to a string if numeric),new line instructions, and have each term concat-enated. The width specified for this field is not thewidth of the longest line but the length of the entireDataTip. If the value entered is too small, the Data-Tip will end when that number of characters isreached. Setting the width too high has no effecton the appearance of the DataTip but requires morestorage space than necessary. The function used inthe query provided to convert numeric values tostrings for use as DataTips (NumToStr) will producenumbers in scientific notation if the values are large.You can get around this effect and specify the num-

ber of decimalplaces using thesprintf function.

STEPS

open a new 2D display(or use the one from theexercise on p. 19 if stillopen) with the ALASKA

raster in the RASTERDB

Project File

with database tablesshown, right-click onthe fragstat table listingin the Display Manager,and choose Properties

scroll to the bottom of thefield list, select the lastentry in the list, thenclick on Add Field

edit the field name to beMultilineDataTip

on the Field Info panel,change the Field Type toString Expression and thewidth to 300

click on [Editexpression], thenon the Open icon,choose Open File(*.qry), and selectMULTILIN.QRY

examine the query andnote the variouscomponents

click [OK] in the Querywindow and [OK] in theProperties window

right-click on the layername and select SetupDataTips

click on [Field], andchoose FRAGSTAT for thetable and MULTILINEDATATIP

as the field, then click[OK]

delete the text in thePrefix field, click [OK],and view DataTips forvarious classes


Attaching Records by CoordinatesSTEPS

open a new 2Ddisplay and selectUS50STATES from the STATES

Project File

expand the layer and thepolygon database andnote that POLYSTATS isthe only table in thedatabase, then chooseDisplay / Close

choose Tools / Database/ Attach

click on [Database] andselect the STATES

database object from theSTATES Project File, thenselect the StatesNametable

click on [Object] andselect the US50STATES

vector object from thesame file

set the Element Type toPolygon

choose Longitude as theX Field and Latitude asthe Y Field

check that the directionfor the X field is set toEast and the Y Field isset to North, and that theProjection is Latitude /Longitude (WGS84 /Geographic)

set the format optionbutton to the right of theReference System fieldto millionths of a degree(DDDdddddd)

click on [Run]

Attributes in any database table (linked or in TNT-mips’ internal format) can be automatically attachedto elements provided each record contains coordi-nate information. You simply select the table thatcontains the attributes to attach and the vector ob-ject and element type that you want the attributesattached to.

For lines or points, records are attached to the ele-ment nearest the coordinates provided. For poly-gons, the coordinates must fall inside a polygon forthe record to be attached. When the process com-pletes, it reports how many records had elementsfound for them and the total number of records. Anyunattached records remain in the table and can beattached in the Display process if appropriate.

All of the tables in the da-tabase are listed for you tochoose from. The se-lected database has onlyone table.

Before running Database Attach, the polygondatabase for the selected vector object has onlya standard attributes (POLYSTATS) table.


Transferring Vector AttributesSTEPS

choose Geometric /Attributes / TransferAttributes

click on [Source] on theVector panel, and selectthe CAPITALCITIES vectorobject from the STATES

Project File

click on [Destination] andselect the US50STATES

vector object

check that Polygon isselected as the destina-tion element and that Allis selected for both thesource and destinationelements

click on [Run]

Just as you had to close the display group in whichyou verified the number of tables in the US50STATES

vector polygon database, you need to exit the At-tach Attributes process before you can start this ex-ercise because of the file locking system in TNTmipsthat protects your data (one process cannot open anobject for writing when another has it open for read-ing or writing).

In the last exercise, you associated attributes withvector elements using the coordinates in each record.You can also transfer attributes from one vector ob-ject to another using element position rather thanexplicitly stated coordinates. You can transfer at-tributes from points, lines, polygons, or labels tothe polygons that contain them entirely or in part.You can transfer attributes from points or lines inone object to the points or lines within a desig-nated radius or the closest point or line in anotherobject. Point attributes can also be transferred tothe closest polygon if the points don’t fall within a

polygon.

Attributes are transferred from points to thepolygons that contain them in this exercise.The number of records transferred is reportedwhen the process completes.

from Database Attach

from TransferAttributes

The stars are the points from whichthe attributes are transferred to thestate outlines. These points repre-sent the capital cities for the conti-nental USA, while the state outlinesare for all 50 states.

The attributes transferred tovector objects can comefrom a raster, vector, or CADobject.


Manually Attaching AttributesYou can assign attributes in any process where youhave a View window and a display manager win-dow. The method is the same in all display pro-cesses although it is described in terms of the mainDisplay process in this exercise. You can also usethese methods in TNT’s Editor, which has additionalfeatures to assist you in assigning attributes as youare creating and / or editing objects.

The table viewing mode to use when assigning at-tributes depends on the attachment type. If the at-tachment type is one element per record, singlerecord view makes attaching attributes easier be-cause every time you click on an element withoutan attached record, you are presented with a newblank record. Tabular presentation is easier to workwith when you are frequently returning to existingrecords for attachment or when you want to selectmultiple elements and attach a single record.

The vector object used for this exercise has a tablein the polygon database that does not yet containany records. The attachment type for the table isOne Record Per Element.

unlabeled corn

Attach elements topreviously addedrecords by selectingthe record and choos-ing the desired attach-ment option.

STEPS

open a new 2Ddisplay, and select theCROPMAP vector object inthe CROPMAP Project File

expand the layer thenshow the tables in thepolygon database, andopen the LandUse table

click on the Selecttool and the ToggleMarked icon inthe View window

click on all the polygonslabeled Corn, thenchoose Record / New /Attached to MarkedElements, and type Corninto the new field

click on theUnmark All icon,then repeat step 4substituting Wheat forCorn

repeat step 5 substi-tuting Beans, Trees,Farm Yard, and Unclassi-fied (?) for Wheat

click on the UnmarkAll icon, click on theShow all recordsicon, click in the

unlabeled corn polygon(shown right), then onthe record selectioncheckbox for Corn, andchoose Record / Attachto Active Element


Assigning Attributes from a PicklistSTEPS

open a new 2D display,and select ROADS from theCB_DLG Project File

expand the layer thenshow the tables in theline database, and openthe CLASS table

switch to single recordview if not already there

click on the Selecttool in the Viewwindow and select one ofthe roads

click on the Selectfrom List icon for theCondition field andchange the assignedcondition

close the table byclicking on the Show orHide Table checkbox inthe Display Manager,then reopen the table

A picklist provides a set of allowable values for aparticular attribute associated with elements in ageometric object. A picklist is opened from thesingle record view of the table you want to containthe attributes. It can be used to assign attributes tonewly added elements, to elements that previouslyhad no attributes assigned, or to change the assignedattributes for selected elements with a single click.

Picklists are automatically available for any stringfield that is also a foreign key field, which meansthat you already have another table that providesthe allowable choices. A picklist can also be cre-ated for you using the picklist wizard that openswhen you click on the Setup Picklist button in theTable Properties window.

If the set of values in the picklist needs to be modi-fied, you simply make the changes in the table thepicklist is generated from just as you would editany other database table. Style samples will beshown in a picklist if the associated attribute is be-ing used to style the geometric object as shown inthe picklist for the Class field shown below.TNTremembers if the picklists for a table were open thelast time you viewed a particular table and will openthe same picklists the next time the table is openedin single record view.

A single table with four pick-lists is shown. Separatetables provide the values foreach of these picklists.

note that the picklist alsoreopened (if you did notclose it before closingthe table)


Finding Elements without AttributesWhen working with a polygonal vector object, suchas a soil map, you generally expect that all poly-gons will have a soil type attached when you aredone assigning attributes. There are many methodsto assign attributes, such as transferring from an-other element type, attaching by geographic loca-tion in a database, or direct attachment in thedisplay or editing process (all of which are describedin this booklet). Regardless of the method, the ques-tion remains the same: how do you know when at-tributes have been assigned to all polygons (or otherelements)? You simply view the object in TNT’sDisplay or Editor process and choose the RMBMoption that selects all elements that lack an attachedrecord in the table you right-click on.

After the elements without attributes have been se-lected, you can view each using the Pre-vious Selected and Next Selected buttonsand assign the appropriate attributes asyou go. That isn’t necessary in this exercise be-cause it is obvious there are two clusters of poly-gons without attached records in the StateCapitalstable (Alaska and Hawaii). You should also havenoticed that only lower Michigan has a record at-tached in this table, sincethe capital falls in thatpart of the state.

You can attach a record to all34 separate Alaska polygonsin one step.

* upper Michigan

lower Michigan

Alaska

STEPS

open a new 2D display,and select US50STATES

from the exercise on p.24

expand the layer thenshow the tables in thepolygon database, andopen the StateCapitalstable

click on the GeoToolboxicon, then click onthe Rectangle tool,inscribe the clusterof polygons thatrepresents Alaska, andclick on [Select Ele-ments] on the Selectpanel in the GeoToolbox

click on the New Recordicon in the State Capitalstable, choose Attachedto Marked Elements andenter Alaska for theState and Juneau for theCapital

use the Rectangle toselect the Hawaiianislands, then repeat step4 but enter Hawaii andHonolulu in the State andCapital fields

click on the Selecttool, click on upperMichigan*, click on theView All Records icon,scroll down and click inthe record selectioncheckbox for Michigan,then choose Record /Attach to Active

Element


Finding Multiple Attached AttributesIt is also a good idea to look for elements with morethan one record attached in an effort to identify at-tachment errors or to provide additional informa-tion about the structure of the table. If only onerecord should be attached to each element, the tabledefinition should reflect this requirement (more onthis topic in later exercises). You may, however,need to clean up data brought in from other sourcesbefore enforcing this restriction. Knowing that ele-ments intentionally have multiple attachments isimportant for selection queries and style scripts be-cause you need to introduce statements that lookfor values in all attached records rather than just thefirst attached record, which is the default.

All hydrological features that are intermittent innature have multiple records attached in the importedDLG vector used in this exercise, one record identi-fies the feature type and one identifies intermittency.You need a query statement that looks at all attachedrecords to assign a different style based on intermit-tency. The necessary script statement to determineif any of the records attached have a specified value(Intermittent) is:

if ("Intermittent" in Table[*].Field).The necessary statement for assigning style basedon the number of records attached (<1) is:

if (SetNum(Table[*]) < 1).

STEPS

open a new 2Ddisplay, and selectHYDROLOGYGI3F08 from theDLG_HYDR Project File

expand the layer and theline database

open the ATTRIBUTES table

right-click on theATTRIBUTES table in theDisplay Manager andchoose Mark Multiply-Attached Elements fromthe menu

click on the Vectoricon in the DisplayManager and examinethe script used for linestyles (click on the Linestab then on [Edit] forStyle By Script)

No elements marked.Multiply-attached ele-ments marked.

Records attached to active element.


Direct or Indirect AttachmentRelational databases in association with spatial dataobjects minimize the amount of work required toattach attributes to the appropriate elements. Theexercises on pages 23–27 all produced direct at-tachments to elements. It is one thing to have theseattachments established automatically, and quiteanother to have to do it yourself on an element byelement basis repeated for each table in the data-base. A relational database can use the direct at-tachments established with one table for all othertables that are related by a primary key / foreignkey relationship.

One table, at least, must be directly attached to ele-ments and one must have a primary key field estab-lished before you can have a functioning relationaldatabase. The Related Only attachment type is fortables that make use of a primary key / foreign keyrelationship to find related records. All other at-tachment types apply to tables with records directlyattached to elements. You should make some effortto understand attachment types and set them appro-priately because they not only affect the number ofrecords you can have attached to elements but howtables behave when objects are merged, extracted,or otherwise manipulated. These topics are dis-cussed in the next few exercises.

The action taken in this exercise to change the at-tachment type of a table from One Record Per Ele-ment to Related Only (using the primary key inanother table) increased the number of polygons thatshow related database information when selected.However, all direct attachments were lost when thissetting was changed.

STEPS

open a new 2D displayand select US50STATES

expand the layer andshow the tables in thepolygon database

right-click on the StatesName entry in the poly-gon table list, chooseMark All AttachedElements, and note thatthe smaller Alaska andHawaii polygons andupper Michigan are nothighlighted

open the StatesNametable and change toSingle Record View

note that the Attached toActive Element button ispushed in

choose Table / Proper-ties, click on the Fieldtab, and pick StateCapitals.State from theRelate to key optionmenu

click on the Table tab,change the Attachmenttype to Related Only,and click [OK]

note that the data typefor the button in step 5has changed, the icon issubtly different (dashedline instead of solid line),and the State field nameis shown in green

click on the Select icon,then click on upperMichigan or one of theAlaskan or Hawaiianislands that werepreviously unattached

OneRecordPer Ele-ment

Related Only


Implied One-To-One AttachmentImplied One-To-One attachment is ideal for tablesthat consist entirely of string expression and com-puted fields so that you can gather and manipulateinformation related to an element from other tableswithout having to manually enter any information(other than the expressions for the fields). You can,of course, include fields that require manual entryif desired.

There is always one record and one record only forevery element with implied one-to-one attachment.As a result, the Mark All Attached, Multiply-At-tached, and Unattached Elements options found forother table types are not on the right mouse buttonmenu in the table list for this table type.

STEPS

right-click on thepolygon row, chooseNew Table, and namethe table PopulationPct

select One record perelement, record numberequals element numberwhen prompted to relatethe records to elements

click on the AddField icon, changethe field name to State,set the Field Type toString Expression andthe Width to 16

click on [Edit Expres-sion], then on theInsert Field icon,choose the StateCapitals table and Statefield, then click [Insert],and [OK] in the Querywindow

click on Add Field,change the name toPop_1990, set the FieldType to Computed, andthe Width to 9

repeat step 4 exceptclick on StatesName forthe table and Population_1990 for the field

click on Add Field,change the fieldname to Pct_USA, setthe Field Type to Com-puted, and the Width to 7with 2 decimal places,then click on [Edit Ex-pression] and enter theexpression shown (left)

click [OK] in the Queryand New Table windows

click on the Select icon,then open the table andselect elements and viewrecords

(StatesName.Population_1990 /SetSum(StatesName[@*].Population_1990)) * 100

You don’t have to enter anyinformation to have therecords filled in using impliedone-to-one attachment andcomputed fields. (There will beblank lines in this table if youview all records, see p. 34.)

You can directlyenter the nameof a field if youknow it or usethe Insert / Fieldmenu.

You canchange thefield name ineither place


STEPS

choose Main/Edit

click on the OpenObject for Editingicon and select theCBSOILS_LITE object fromthe CBUTTE Project File

expand the layer and thepolygon database in theLayer Manager

right-click on the CLASStable in the list, chooseProperties, and checkthat the Attachment Typeon the Table Info tab isset to One Record PerElement, then click [OK]

open the CLASS table,and note the number ofrecords

click on the AddLine icon, then clickat the upper left andlower right to produce adiagonal line across theobject, and click on [Add]

note the number ofrecords in the table afterthe line is added thenclick on the Undoicon (View window)

repeat steps 4–6 exceptin step 4 set the Attach-ment Type to NoRestriction

note the number ofrecords in the table afterthe line is added

choose Object / Exit anddiscard the changes

Other Attachment TypesThe No Restriction attachment type lets you attachmultiple records to multiple elements. The One El-ement Per Record attachment type prevents you fromattaching a record to more than one element andtells you that the first attachment will be broken ifyou proceed with attachment of a second element.Thus, when all elements have attributes assigned,you will have at least as many records as elements(more if more than one record is attached to an ele-ment). The One Record Per Element attachment typelets you set up one record for each attribute valueand attach it to all elements with that value, such aspolygons of a particular soil type. Trying to attacha second record to an element will break the firstattachment. The One-To-One attachment type letsyou have at most one record attached to an elementand only one element attached to a record.

You can choose to be prompted to enter attributevalues when elements are added or split in TNT’sEditor. You can also choose to have a selected (“de-fault”) record attached without prompting if you areadding multiple elements with the same attributevalue.

One Record Per Element No Restriction

before adding lineto split polygons

The attachment typeaffects the number ofrecords after anyoperation that splitselements, such asediting, merging, orcombining vectorobjects.

before split

after splitafter split


Intersectinghydrology(blue) androads(brown)createspoints withattributesfrom both.

Demoting Attachment RestrictionsThe attachment type established in a table defini-tion determines how element attributes are handledduring editing and other object manipulations, suchas merging and different types of combinations. TheNo Restriction attachment type may cause unex-pected results when editing or combining objectsbecause you can end up with many more recordsthan you started with, which can be disconcerting.If such results were not what you intended, you candelete duplicate records in the Database Editor.

The one record per element attachment type is gen-erally used for tables with a single, categorical fieldthat is a primary key or with a number of fields thatprovide summary data for all members of the namedclass. In such tables you have one record for eachattribute value that is attached to all elements withthat value. The number of records in the table tellsyou how many different attribute values you havefor the elements in an object (provided there are nounattached or duplicate records). Some vector com-binations, such as line-to-line intersect (which cre-ates an output vector of points at the locations thelines in the input vectors cross) produce the mostuseful results when the attributes from both inputvectors are maintained. To produce such a resultwhen tables are joined, the attachment type of theoutput table must often be demoted to No Restric-tion from the more stringent One Record Per Ele-ment of the input tables. If you do not want theattachment type automatically demoted, choose notto join the tables when the output object is produced.

STEPS

choose Geometric /Combine

set the Operation menuto Intersect (AND)

click on [Select] in theSource panel andchoose HYDROLOGY fromthe CBUTTE Project File

click on [Vector] in theOperator panel andselect ROADS from thesame file

set the Polygons to Nonein the Source panel

select Line in theOperator panel

set the Table JoiningOptions to If Same TableStructure (2nd option)

click on [Run]

name the output objectINTERSECTPOINTS

open a new 2D group inDisplay and select theINTERSECTPOINTS object

open the LayerControls, click on[Styles] and choosePOINTSTYLE in the CBUTTE

Project File

click on the Points tab,set the style to By Script,click on [Edit], then clickon the Open icon,choose Open RVCObject and selectSTYLESCRIPT from theCBUTTE Project File

once displayed, click onthe Select icon, thenclick on points toview their attributes; alsonote the attachment typein the table properties


Database tables are often assembled from a numberof sources at different times and may have morethan the single redundant field needed to establishindirect attachments. At some point you may wantto consolidate and eliminate tables or otherwise ma-nipulate your database.

You can use the Database Editor to build directattachments for you rather than having to establishthem manually if the attachment type is RelatedOnly or if thetable containsX-Y coordi-nate fields.Direct attach-ment by X-Yc o o r d i n a t efields with the Database Editor provides an alterna-tive method to that used in the exercise on page 19for attaching records. (You first have to use the AddTable function on the Make Table / Form icon menuif you don’t use the Attach Database process.)

Even though the records have X and Y coordinatesin this example, you want to use the Currently Re-lated option for establishing attachments or youwill once again find that only the largest polygonsremain attached for Alaska and Hawaii and that up-per Michigan will no longer be attached to a record.

In general you would not take the steps in this exer-cise unless you intended to delete a related table.You might want to delete tables for a variety ofreasons, such as those already mentioned or publicdistribution of an object with some proprietarytables in its database that should be deleted beforedistribution. You can delete tables from the rightmouse button menu for the table in the DatabaseEditor or a display Manager window or from theTable menu in the table itself.

Building Direct AttachmentsSTEPS

choose Tools / Database/ Edit from the TNTmenu* and select theus50states object whenprompted

choose Polygon in theSelect window and click[OK]

click on the Relateicon

place the cursor over theInternal box, click the leftmouse button, drag thecursor to theStatesName table, andrelease

set the Attach menu toCurrently Related andthe Attachment Typemenu to One record perelement, then click [OK]

exit the process

* If using TNTedit or TNT-view, you need to launchthe Display process, selectthe US50STATES object, showdetails for the layer andchoose Edit Relations fromthe RMBM for the polygondatabase.

afterdirectattach-ment


STEPS

choose Main / Display ifnot already open andadd the US50STATES objectto a new 2D display

open the StateCapitalstable in the polygondatabase and chooseTable / Properties

highlight Capital in thefields list then followsteps 5–8 on page 30(instead of entering theexpression in step 7,enter PopulationPct.Pct_USA or use Insert /Field to enter it for you)

in tabular view of theStateCapitals table, right-click on the field namebutton for Pop_1990,choose Make FieldPermanent, then click on[Yes] in the Verify window

click on the Pct_ USAfield label, choose Field /Make Permanent, andclick on [Yes] in the Verifywindow

note that the field namesare no longer blue

return to the Propertieswindow and note that thefield type for these twofields has changed fromComputed to Floating-point

click on the Selecticon, open thePopulationPcttable, selectsome elementsand note that thecomputed andpermanentvalues agree

Making Computed Fields PermanentComputed fields are a powerful database featurethat lets you combine the information in one ormore tables to provide a new slant on the data. Forexample, raw population data can become percentpopulation data, as in the table you created on page30. In cases where the fields used in the expressionfor the computed field are continually updated, youwant them to be recalculated every time you viewthe table. In other cases, the fields that feed into thecomputed field expression are unchanging and thevalue may as well be frozen once the computationis made.

The computed fields in the PopulationPct table arebased on 1990 population data, which isn’t likelyto change, so the values in these fields could bemade permanent. However, these fields currentlyexist in an Implied One-To-One table that has manyblank records because of the unclassified islandpolygons off the coast of Florida and a number ofother states. So we’ll add this information to theStateCapitals table before making it permanent.

A table with computed fields may pull together allthe information of interest to you from a variety ofother tables, which may no longer be needed onceyou have the computed values. You need to makethe computed fields permanent before deleting anytables used in their expressions. Most field ma-nipulation functions are available only from theField menu or the right mouse button in tabularview. If selecting from the Field menu, you need tofirst select a field by clicking on the field label sothe menu items are active.

A Verify window opens foryou to confirm you want tomake this irreversiblechange.


Default Record in the EditorSTEPS

choose Main / Edit

click on the AddReference Layericon and select the CIR_4object from the DAWSON

Project File, click on theCreate Object icon,choose Vector, andclick [OK] in the NewObject Values window

right-click on the lineentry for the new vectorand choose DefaultRecord

click on [New Table],confirm User-Defined,then enter FEATURES as thename

select One Record PerElement

set up the table so it hasa single string field (Width18) that is the primarykey

click [OK] in the tabledefinition and Select Tablefor Prompt windows

type county road into thefield in the Default Recordwindow and click [OK]

click on the AddLine icon and add one horizontal and threevertical lines that followthe roads as shown

repeat step 3, selectFEATURES table, andchange the field entry tointermittent canal

add a line for the canal asshown (turn snapping off)

change to the Selecttool, open the Fea-tures table, and view theline attributes

You can set a “default” record for each element typein TNT’s Editor. The default record is attached toevery element of that type added until you set thedefault to no record or turn on the tabular viewdefault record option. Assignment of a defaultrecord by the method described in this exercise isbest suited for adding a number of vector elementsof the same type, such as when photointerpretingcounty roads. Assignment of a default record is themethod of choice for new vector ob-jects when you will be creating anew table for attribute assignment.Setting the default record in tabularview (next exercise) is a betterchoice when the records you want to attach alreadyexist. You can also choose to be prompted to selecta record when an element is added.

When the attachment type is One Record Per Ele-ment, only one record will be created for each at-tribute value entered. One record will be createdfor each element added for any other direct attach-ment type.

Open the table and selectelements to confirm attach-ments are as expected.

Entering a new attributevalue creates a newrecord when the nextelement is added.


Setting Tabular View Default RecordSTEPS

remove the New Vectorlayer created in theprevious exercise (keepthe reference layer open)

click on the OpenObject for Editingicon and select the TGR_EXTRACT object in theDAWSON Project File; openits Vector Layer Controlsand set the lines style toClassStyle1

choose Setup /Preferences(Editor-LayerManagerwindow), clickon the Othertab, and toggleon the Enabletabular view defaultrecord option

expand the vector layerto show the line databasetables, and open theCLASS table

click on the Add Linetool then, with all recordsshowing, click in theSelect Record boxfor the A31 class

add lines just as inthe last exercise(roads only)

There are two different ways to set up a defaultrecord for attachment, so you need to have somemeans of specifying which you want to use. Theact of setting up a default record from the RMBM(previous exercise) is sufficient to turn on thatmethod. You need to turn on a toggle button in thePreferences window to use the tabular view defaultrecord. Once this option is turned on, it attachesthe selected record to each element added. Select-ing a different record changes the default record

attached toe l e m e n t swhen added.Any recordselected priorto choosingan add ele-ment tool is

cleared when you initially choose to add elements,but persists as you change elements added if stillapplicable (default line attributes are assigned topolygon lines).

When elements are displayed by attribute, you cantell immediately if added elements have been as-

signed to theexpected classbecause theyare drawn inthe assignedstyle as soon asthey are added.

The record currentlyselected will be attachedto the elements added.

before after


Nodes with AttributesPolygonal and planar vector topology require anode at every line element end and intersection.Nodes serve an important topological function, buttheir existence depends on the line elements. Thus,as you delete adjoining line elements, the node maybecome an “excess node” and be subject to dele-tion by the Remove Excess Nodes filter. If all linesemerging from a node are deleted, the node is auto-matically deleted. You can protect a node from suchautomatic deletions in one of two ways: attach oneor more database records or use the Convert Nodeto Point tool. After attributes are attached, nodesdraw in the designated point style. Note that in thisexercise, the new point is redrawn in the “all same”style for points.

A variety of attributes can be associated with nodes.In this exercise, you assign the ownership of thesurrounding land to a node. You might also want toidentify a feature that happens to occur at a line in-tersection. Generally, attributes assigned to nodesshould identify a property of the node that will re-main if the lines are deleted.

Any table you create for nodes becomes part of thepoint database. When you show the tables for nodesand the tables for points, they are exactly the same.These tables are simply listed twice (once underpoints and again under nodes) for convenience.

If these two lines are deleted, the node is also deleted.

If these four lines are deleted, the former node remains.

STEPS

still in Editor, remove thelayer from the lastexercise (saving changesif desired), then openthe MERGED object inthe DAWSON Project File

expand the layer andshow tables for pointsand nodes

right-click on the nodedatabase line, andchoose New Table

name the table OWNERSHIP,set to One record perelement, and add asingle string field (width20); note the new tableappears under bothpoints and nodes

open the new table,choose the Selecttool, and click on thenode at the intersectionin the middle of theobject

click on the NewRecord icon, chooseAttached to ActiveElement, and enterKloepping in the newrecord

select one of the fourlines that emerge fromthe converted node, turnon the Delete oper-ation, and click onActive

also delete the otherthree lines that emergefrom the new point

delete the two linesthat emerge from thenode at the top center

note what remains at theformer line intersections


X-Y Plots of Numeric FieldsYou can select any two numeric fields and plot themagainst each other. The first selected field becomesthe X axis and the second field provides the Y val-ues. Fields are selected by clicking on the field namein tabular view (the second field is selected by hold-ing down the <shift> key and clicking on the sec-ond field name).

A variety of statistical tools to assist with interpre-tation of the plots are also provided. You can add aregression line, draw a line that connects the pointsin numeric order, spline that line, determine the cen-

troid for all the data points, oradd a Hough Transform of thedata. Each of these componentsis color coded on the menu anddisplayed in that color when se-lected.

STEPS

choose Main / Display,open a new 2Ddisplay, andchoose the US50STATES

vector object from theSTATES Project File

expand the layer and thepolygon database andopen the StatesNametable

in tabular view, click onthe Population_1990 fieldname, then hold the<shift> key and click onthe Latitude field name

choose Field / Plot / XYPlot in the tabular view

click on the Show /Regression toggle in theXY Plot window

try the other options onthe menus

Adding the regres-sion line makes ap-parent the smallnegative correlationbetween latitude andstate population inthe USA.

State Population (X)vs Latitude (Y)

The strong, positive correlation between the numberof males and the number of females living in capitalcities in the USA is quite apparent even without theregression line.

X axisfield name Y axis

field nametablename


Histogram of Numeric FieldThe TNT products can also create a histogram forany single selected field. The histogram provides agraphical representation of the distribution of val-ues for the selected field. More specifically, thehistogram presents the number of records that haveeach of the values in the selected field. The num-ber of records is presented on the Y axis and thevalue distribution is along the X axis.

As with X-Y Plots, you can save a snapshot of thewindow contents as a raster in Project File format.You can also save the histogram as a text file. Youcan display the histogram as an outline (initial de-fault), as bars, or as a strip. The histogram can havea linear or logarithmic scale and may represent in-dividual values or be cumulative. You can alsochoose whether or not to label the histogram,whether the labels are plain or in a box, and howlarge the labels are. Your last chosen display op-tions are remembered and used for the next timeyou choose this feature.

STEPS

open a new 2D display,and choose theCAPITAL_CITIES vectorobject from the STATE

POINTS Project File

expand the layer and thepoint database and openthe Population table

in tabular view, click onthe POP field name

select Field/Plot/Histogram

try the different options

repeat steps 3 and 4 forother fields

histogram with default settings cumulative option turned on

strip display mode logarithmic, cumulative strip


Saving Tables as CAD ObjectsIn addition to saving database tables, selectedrecords, or statistics in internal or other databaseformats, you can save them in CAD format so thatdatabase information can be incorporated as part ofa layout. Unlike legends, which provide drawingstyle samples for a single attribute of the object il-lustrated, you can present the attributes in all fieldsusing this feature. Tables can be used in place of alegend if desired since the style field is included inthe CAD object if shown in the table.

When you save a table as a CAD object, you havethe option of saving all records or only selectedrecords and including or excluding fields you havehidden. A style object and style assignment table

are created so the appear-ance of the CAD objectmatches your display op-tions for the databasetable. Thus, if you haveselected interleaved col-

ors, your CAD object will have the same colors andinterval as the database tabular view.

You can change the assigned colors and fonts, butthe Use Element Size toggle for text must remain

STEPS

in the Display process,click on the OpenDisplay icon, andselect the WesternStateslayout in the STATES

Project File

expand the WESTERNSTATES

vector in either Group 1or 2, then expand thepolygon databaseand open the Populationtable

in tabular view, chooseTable / Save As and setthe format to CADSnapshot, click [OK] andname the outputWESTERNSTATES,change the font ifdesired then click[OK] in the StyleEditor window

click on Group 3 tomake it the activegroup, then on theAdd Objects icon, andselect the WESTERNSTATES

CAD object just created

view the resultson so the text fits the table structureof the CAD object. The size at whichthe CAD object is inserted in a layoutshould be controlled by the zoom fac-tor in the Group Settings window, notby trying to adjust the size of indi-vidual elements.

You may have to adjust the relativezoom of Group 3 in the Group Settingswindow if your layout does not appearas shown after adding your CAD ob-ject. In this example, you would notwant to show the style field in the tablebecause the style would apply only toone of the two theme maps.


The ability to link to .dbf files in all TNT productsand to save tables or selected records in any ODBCformat you have set up or .dbf format in TNTmips,TNTedit, and TNTview provides a powerful meansof sharing data between applications. For example,consider a vector created in TNTmips that has at-tributes that include computed fields. You have ex-ported the vector to a shapefile for use by others inArcView. Circumstances change and necessitatealteration of the expression for the computed field.You can make that change in TNTmips, choose Table/ Save As, set the format to dBASE III/IV, and re-place the existing .dbf file associated with theshapefile. You do not need to re-export the vectorobject. This technique requires a one-to-one rela-tionship between elements and records.

Another possibility is that you have a vector objectin any TNT product that has an attribute table linkedto a .dbf file that was created from a model in aspreadsheet program, such as Microsoft Excel. Youcan vary the model in the spreadsheet program, savethe results in .dbf format and immediately examinethe effect of the alteration in the Display process.For example, you may have a model that determineswhat areas you should spray for weeds or pests thatincorporates severity of the problem, potential re-turn, and the dollars you have to spend. When theamount you have to spend changes, you simply enterthe new dollar amount in the model, redeterminethe areas to spray, and save the result as .dbf. Thenext time it is drawn in TNTmips, the areas will beupdated.

These Save As options are found on the same menuas Save As CAD Snapshot, which is described in theprevious exercise. Although you can save a CADsnapshot in TNTmips Free or save to a new table inProject File format, you cannot save to external filetypes.

planting rates

Change the expression forthe theme mapped fieldbased on new information(different recommendedrates for the same or a dif-ferent herbicide).

altered thememap fromchanged ex-pression

theme mapfor originalexpression

Sharing Attributes between Applications


Geotagging Digital PhotosGeotagging is the process of adding geographiccoordinates to digital photos. There are a numberof ways to accomplish geotagging in TNTmips. Youcan directly enter coordinates for each of your photolocations, you can use a GPS log file and the closestor an interpolated position, or you can use a refer-ence image.

Geographic coordinates are fairly easily obtainedif you have access to the Internet. Google Earthwill fly you to any location and provides geographiccoordinates for your cursor location. You can alsouse Web Map Service (WMS) layers in TNTmipsand read the coordinates.

Digital photos are generally much bigger than willfit in TNTmips Free. The Raster Extract process inTNTmips was used to prepare small pieces of thedigital photos used in this exercise, which were thenexported to JPEG so they could be used in the Cre-ate Geotagged Image Database process.MicroImages’ geoprovisioning site (www.

geospatialgateway.com) wasused to generate the referencephoto.

STEPS

choose Tools / CreateGeotagged ImageDatabase

click on the Add Imagesicon and selectColumbiaRiver.jpg andVistaHouse.jpg

enter 45.539522 forLatitude and -122.2443for Longitude forVistaHouse.jpg

enter 45.574878 forLatitude and-122.177611 forColumbisRiver.jpg

click on the Data-base Pinmap icon,then on Input Raster, andselect 685.jp2

zoom up near the lowerleft of the image

(exercise continues on nextpage)

choose thisoption to embedphotos in table


Viewing Geotagged Image Tables

click on the VistaHouseentry in the CreateGeotagged ImageDatabase window toactivate the Point tool forthat point in theDatabase Pinmapwindow

reposition the point tocenter on the featureand right-click

turn on the Embedimages in table asBLOBs button

click on [Run] and savethe database

open a new 2D Displayand select 685.jp2

click on the Add Pinmapicon and select thedatabase you justcreated

click on the points taband note that the X andY fields are alreadyselected

click on the Symbol tabthen on the Style button

select Circle (filled) andchange the color to onethat will contrast well

click on the DataTip taband note that the imagethumbnail is alreadyselected

open the GeotaggedImages table

pause the cursor overthe Image field in one ofthe records

double-click on theImage field in one of thereccords

(continued from precedingpage)

Once you have geotagged your photos with the Cre-ate Geotagged Image Database process, they areready to to use in the Display process as a pinmap.The X and Y fields are automatically set, as is theDataTip. The thumbnail of your digital photo is theautomatically set DataTip for your pinmappedpoints.

You can double-click on the Image field in the tablemade by the Create Geotagged Image Database pro-cess to open a viewing window for the photo. Thiswindow has zooming tools and lets you step throughall the images in the table. The window can beresized and the scroll wheel is also active for zoom-ing in and out. If there is metadata with the photo, itcan also be opened from this window. If the photo isrepresented by the directory path rather than em-bedded, the DataTip is the full size image ratherthan the thumbnail.

Double-clicking on the imagefield opens a viewer window.

The pin map-ping param-eters areautomaticallyset up by thegeotaggingprocess.

Advanced Software for Geospatial Analysis

MicroImages, Inc.

MANAGING

ATTRIB

www.microimages.com

Indexattaching records by coordinates .......... 23CAD snapshots ....................................... 40computed fields ......................... 30, 34, 41Database Editor ........................... 4, 19, 33DataTips ........................................... 20–22.dbf files ................................................... 41default records (Editor) ................... 35–36demoting attachment restrictions ........ 3 2direct attachment .............................. 4, 29edit table definition .................................. 5elements without attributes ................... 2 7field options ............................................ 14field width ................................................ 1 4geotagging digital photos ................ 42–43grid lines ................................................... 13implied one-to-one attachment ............ 30indirect attachment ........................... 5, 29LegendView ................................................ 6manual attachment ................................. 25multiple attribute attachments ............. 2 8

one record per element .......................... 31picklists .................................................... 2 6primary key ...................................... 4, 5, 7raster attributes ................................ 18, 19regression line ......................................... 38related only ................................. 5, 15, 29right mouse button menus ..................... 15scrollbar tips ............................................ 13select by query .......................................... 7selecting elements ......... 7, 11, 12, 14, 27single record view ..................................... 8sorting ...................................................... 16system tables ........................................... 1 7table viewing preferences ...................... 1 3tabular view ............................................... 9transferring attributes ............................ 2 4vector combinations .............................. 32viewing attributes ........................ 7–11, 37X-Y plots ................................................. 3 8

MicroImages, Inc. publishes a complete line of professional software for advancedgeospatial data visualization, analysis, and publishing. Contact us or visit ourweb site for detailed product information.TNTmips Pro TNTmips Pro is a professional system for fully integrated GIS, image

analysis, CAD, TIN, desktop cartography, and geospatial database management.

TNTmips Basic TNTmips Basic is a low-cost version of TNTmips for small projects.

TNTmips Free TNTmips Free is a free version of TNTmips for students andprofessionals with small projects. You can download TNTmips Free from Micro-Images’ web site.

TNTedit TNTedit provides interactive tools to create, georeference, and edit vector,image, CAD, TIN, and relational database project materials in a wide variety of formats.

TNTview TNTview has the same powerful display features as TNTmips and is perfectfor those who do not need the technical processing and preparation features ofTNTmips.

TNTatlas TNTatlas lets you publish and distribute your spatial project materials on CD orDVD at low cost. TNTatlas CDs/DVDs can be used on any popular computingplatform.

TNTserver TNTserver lets you publish TNTatlases on the Internet or on your intranet.Navigate through geodata atlases with your web browser and the TNTclient Java applet.

tutorial: managing geoattributes · the first exercises in ... tntmips pro, tntmips basic, and...

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