10 geodata analysis

8/10/2019 10 Geodata Analysis

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Geodata analysis

Riccardo De Filippi

[email protected]


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AnalysisPurpose & Methods

Queries and reasoning

Measurements

Transformation

Data mining

Descriptive summaries

Optimization

Hypothesis testing

Vector

analysis

Raster

analysis

Combined

analysis


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Operations in vector

What is?

What is its relation to otherentities?

Where is it?

Attribute

Spatial topology

Distance/location

Feature analysis

Select

Create


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What is it: Attribute operators

Logical operations attributes of one or more entities

individual entities

Mathematical operations new attribute

math calculation

Statistical analysis descriptive stat

stat software

Numerical models complex sets of mathematical functions that represent physical process


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Spatial operators

Relational operators:- Testing spatial relationships between geometries

- Result is a boolean value, no new geometries are created

Topological operators:- Support for editing geographic features

- Result is a new geometry based on a logical comparison between

geometries


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Vector analysis: Relational operators

Relational operators: Equals

Contains

Within Crosses

Overlaps

Touches

Disjoint


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Vector analysis: Relational operators(3)

Contains Within

Zeiler (1999)


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Vector analysis: Topological operators

Topological operators: Buffer

Clip

Convex hull

Cut

Difference

Intersect

Symmetric Difference

Union


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Zeiler (1999)

Buffer Clip

Topological operators (1)


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Zeiler (1999)

Difference Intersect

Topological operators (3)


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Interaction


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Cell processing

Every cell of the raster is processed


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Raster Map Analysis

Map query Boolean/logical operations:

And, Or, XOr, Not, >, >=, =, ,


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Raster Functions

Trigonometric sin, cos, tan, ...

Exponential ax, ex

Logarithmic log, ln, lg, ld

Relational >,


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Raster functions: Spatial

application

Zeiler (1999)


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Local functions

McCoy et al. (2002)


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Local function : application case

2003 2004 2005

rain

Local mean or minimum


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Focal functionsMcCoy et al. (2002)


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Focal function: application case

5 6 31

1 3 3.4

6 1.5 3

Burrough (1998)


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Zonal functions

Quelle: ArcGIS 9.0 Desktop Help


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Global functions


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Application function 1First and higher derivatives

- slope- aspect- plan curvature

- profile curvature

Quelle: ArcGIS 9.0 Desktop Help

DTMslope aspect


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Application function 2

Viewsheds, shaded relief, irradiance

Zeiler (1999)

DTM hillshade

combin

ed


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Dilation, spreading, dispersion - fire spreading

- oil dilation and translocation

- soil solute dispersion frompoint source

Zeiler (1999)


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Spatial transformation - translocation

- scaling, distension, stretching

- rotation

- distortion

Zeiler (1999)


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Raster analysis: application 5

Surface topology, drainage network, sun- Slope, Aspect- Hydrology- Sun radiation.

DTM

flow accumulation

watershed & subwatersheds

Sources: Weisshaidinger; Hebel


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Proximity - Euclidian distance - Travel time

Zeiler (1999)


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Least-cost path analysis

Zeiler (1999)


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Raster Operator

Arithmetic

[Inlayer1] + [Inlayer2] / 2

BooleanWhere 0 in layer1 and layer2

RelationalInlayer < 3


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Process diagram (flowchart) Input data

Process

Intermediate data

Output data

Line Line Selection

SelectData processing

Input Intermediate

ProcessData processing

Output

Process


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Process diagramms

SummarizeTable.dbf

Summar

ize

Answer 5 statistics on 3 road classes

Answer 3, 4, 5 Shortest, Longest, Sum of rivers?

1_Klass 2_Klass 3_KlassBach Layer

Select & Statistic

Updated length R & R

Update line length: quality check! not recalculated

Geocorrected area RoadsRivers

Test Area xy

Modify feature

Answer 2 How many line features are within test ?Clipped Roads and Rivers

Clip


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Practice

QuantumGIS visualization, map editing

Grass data processing engine, data editing


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References Burrough, P.A., and R.A. McDonnell, 1998. Pronciples of Geographical

Information Systems. Oxford: University Press.

Longley, P.A., M.F. Goodchild, D.J. Maguire, D.W. Rhind, 2001. Geographic

Information Systems and Science. Chichester, UK John Wiley & Sons.

Zeiler, M., 1999. Modelling our World: The ESRI Guide to Geodatabase Design.

Redlands, Ca: ESRI Press.


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References Longley, P.A., M.F. Goodchild, D.J. Maguire, D.W. Rhind, 2001. Geographic

Information Systems and Science. Chichester, UK John Wiley & Sons.

SNV, 1998. SN 612030: Vermessung und Geoinformation INTERLIS

Modellierungssprache und Datentransfermethode. Winterthur, CH:

Schweizerische Normen-Vereinigung.

Swisstopo, 2005. Bundesamt fr Landestopographie. Bern, CH: Swisstopo.

Avaliable at: www.swisstopo.ch. Zeiler, M., 1999. Modelling our World: The ESRI Guide to Geodatabase Design.

Redlands, Ca: ESRI Press.


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References Department of Geography, 2005. Geographic Information Technology Training

Alliance (GITTA). Zurich, CH: University of Zurich. Avaliable at: www.gitta.info.

Burrough, P.A., and R.A. McDonnell, 1998. Pronciples of Geographical

Information Systems. Oxford: University Press.

Fischer, M., and P. Nijkamp, 1993. Geographic Information Systems, Spatial

Modelling and Policy Evaluation. Berlin and Heidelberg: Springer Verlag.

Longley, P.A., M.F. Goodchild, D.J. Maguire, and D.W. Rhind, 2001. Geographic

Information Systems and Science. Chichester, UK: John Wiley & Sons.

Tomlinson, R., 2003. Thinking about GIS: Geographic Information System

Planning for Managers. Redlands, Ca: ESRI Press.

Zeiler, M., 1999. Modelling our World: The ESRI Guide to Geodatabase Design.Redlands, Ca: ESRI Press.


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ReferencesMcCoy, J., K. Johnston, S. Kopp, B. Borup, J. Willison, B. Payne,

2002. Using ArcGIS Spatial Analyst, - GIS by ESRI. Redlangs,Ca: ESRI Press.

Swisstopo, 2005. Bundesamt fr Landestopographie. Bern, CH:Swisstopo. Avaliable at: www.swisstopo.ch.

Zeiler, M., 1999. Modelling our World: The ESRI Guide to

Geodatabase Design. Redlands, Ca: ESRI Press.

10 geodata analysis

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