Functions

BUS 782

Types of Functions

• Built-in functions:– Financial– Date & time– Math & statistical– Database– Lookup– Logical– Information: IsBlank, IsNumber, IsText– Text– Etc.

• User-defined functions

If Function

Determine action based on condition

Examples

• Simple condition:– If total sales exceeds $300 then applies 5% discount;

otherwise, no discount.

• More than one condition:• Taxable Income < =3000 no tax• 3000 < taxable income <= 10000 5% tax• 10000 < taxable income <= 50000 10% tax• Taxable income > 50000 15% tax

• Complex condition:– If an applicant’s GPA > 3.0 and SAT > 1200: admitted

Comparison• Less than: <• Less than or equal: <=• Greater than: >• Greater than or equal: >=• Equal: =• Not equal: <>

– At least: >=– At most: <=– No more than: <=– No less than: >=

• A comparison returns True/False.– Example:

IF Function

• =IF(condition, ValueIfTrue,ValueIfFalse)

• Example: – Tuition: If total units <= 12, then tuition = 1200

» Otherwise, tuition = 1200 + 200 per additional unit

• Example: Compute weekly wage. Overtime hours are paid 50% more than the regular pay.

• Example: Tax rate is based on married status:– Single: 15%– Married: 10%

• Example: A restaurant charges service fee based on this rule: 15% of the check amount with a minimum of $2.

Exercises

• 1. How to determine an integer entered in a cell is an even number or an odd number?

• 2. The average of two exams is calculated by this rule: 60% * higher score + 40% * lower score.

• 3. An Internet service provider offers a service plan that charges customer based on this rule:

• The first 20 hours: $10• Each additional hour: $1.5

Calculating Conditional Counts and Sums

• COUNTIF(range, criteria)– Range of cells– Criteria: expression that define which cells are

to be counted.

• SUMIF(range, criteria,[sum_range])– Sum_range: The cells you want to sum. If

omit, Excel will sum the values in the range argument.

Example

1. How many employees earn more than 5000?

COUNTIF(B2:b4,”>5000”)

2. Compute the total salary of employees earning more than 5000.

SUMIF(B2:b4,”>5000”)

3. How many employees’ name begin with “P”?

COUNTIF(A2:A4,”P*”)

Complex Condition

• Examples:– A theater charges admission fee based on

customer’s age:• 12 <= Age <= 65: Fee = $5• Otherwise: Fee = $3

– X University admission rules:• If GPA > 3.5 or SAT > 1500: Admitted

– Y University admission rules:• If GPA > 3.0 and SAT > 1200: Admitted

Logical Operators: AND, OR, NOT

• AND• Cond1 Cond2 Cond1 AND Cond2

T TT FF TF F

• OR• Cond1 Cond2 Cond1 OR Cond2

T TT FF TF F

• NOT• Cond NOT Cond

TF

Examples

• Write a complex condition for: 12 <= Age <= 65• Use a complex condition to describe age not

between 12 and 65.• X <= 15 is equivalent to: X<15 AND X =15?

(T/F)• This complex condition is always false:

– X < 5 AND X > 10

• This complex condition is always true:– X >= 5 OR X <= 10

AND Function/OR Function

• =AND (cond1, cond2, …, cond n)– Up to 30 conditions– True if all conditions are true– False if any condition is false

• =OR (cond1, cond2, …, cond n)– True if any condition is true– False if all conditions are false

• The rules to compute employee bonus are: – If JobCode = 1 and Salary < 50000, then

bonus = 30% * salary– Otherwise, bonus = 20% * salary

Note: Change the rules to OR

Nested IF and Complex Condition

Nested IF

• Example:– Rules to determine bonus:

• JobCode = 1, Bonus=500• JobCode = 2, Bonus = 700• JobCode = 3, Bonus = 1000

– In C2: If(B2=1, 500, If(B2=2, 700, 1000))

JobCode= 1

Or <> =1

JobCode=2 Or <> 2

1

2

3

Example• Electric Company charges customers based on

KiloWatt-Hour used. The rules are:– First 100 KH, 20 cents per KH– Each of the next 200 KH

• (up to 300 KH), 15 cents per KH– All KH over 300, 10 cents per KH

What if we have more than 3 conditions

• Example: Bonus– JobCode = 1, Bonus = 500– JobCode = 2, Bonus = 600– JobCode = 3, Bonus = 700– JobCode = 4, Bonus = 800– JobCode = 5, Bonus = 1000– …

• Other functions:– Table lookup

Example

• State University calculates students tuition based on the following rules:– State residents:

• Total units taken <=12, tuition = 1200• Total units taken > 12, tuition = 1200 + 200 per

additional unit.

– Non residents:• Total units taken <= 9, tuition = 3000• Total units taken > 9, tuition = 3000 + 500 per

additional unit.

Resident or Not

Units <= 12 or Not

Units <= 9 or Not

Complex Condition

• University admission rules: Applicants will be admitted if meet one of the following rules:– 1. Income >= 100,000– 2. GPA > 2.5 AND SAT > 900

• An applicant’s Income is 150,000, GPA is 2.9 and SAT is 800. Admitted?– Income >= 100,000 OR GPA > 2.5 AND SAT >900

• How to evaluate this complex condition?

• Scholarship: Business students with GPA at least 3.2 and major in Accounting or CIS qualified to apply:– 1. GPA >= 3.2– 2. Major in Accounting OR CIS

• Is a CIS student with GPA = 2.0 qualified?– GPA >= 3.2 AND Major = “Acct” OR Major = “CIS”

• Is this complex condition correct?

NOTSet 1: Young: Age < 30

Set 2: Rich: Income >= 100,000

Young Rich

Condition with Not

• University admission rules: Applicants will be admitted if meet all the rules:– 1. SAT > 900 OR Income >= 50,000– 2. Not GPA < 2.5

• Condition:– SAT > 900 OR Income >= 50,000 AND Not GPA < 2.5– Correct?

Order of Evaluation

• 1. ()

• 2. Not

• 3. AND

• 4. OR

Examples

• SAT = 800, Income 60,000, GPA 3.0, admitted?

– (SAT > 900 OR Income >= 50,000) AND Not GPA < 2.5

• A=2, B=3

– (A=3 OR NOT (B < A)) AND B=A+1

• Rules to calculate employee bonus are:– If JobCode = 1 AND Salary < 5000 OR Sex = “F”

Bonus = 10% * Salary– Otherwise: Bonus = 8% * Salary

Practices

• 1. Change the rules for bonus to:– If Sex = “F” AND (JobCode = 1 OR JobCode = 2)

then bonus = 10% * Salary– Otherwise, bonus = 8% * Salary

• 2. Change the rules to:– If JobCode = 1 AND Salary < 5000 OR Sex = “F”

Bonus = 10% * Salary– Otherwise: Bonus = 8% * Salary

• Use a complex condition to describe numbers:

20 50 100

Set 1: Young: Age < 30Set 2: Rich: Income >= 100,000 Set 3: Smart: GPA > 3.5

Young Rich

Smart