Functions BUS 782

What are functions? Functions are prewritten formulas. We use functions to perform calculations. Enclose arguments within parentheses. Arguments are values on which you want to perform the calculation. Example: PMT function

Types of Functions Built-in functions: –Financial –Date & time –Math & statistical –Database –Lookup –Logical –Text –Etc.

Examples of Using Math Functions: Quotient and Mod Quotient: Quotient(Dividend, Divisor) Remainder function: MOD(Dividend, Divisor)

Return the Smallest Number of Coins Examples: 26 cents: 1 Q, 1 P 57 cents: 2 Q, 1 N, 2 P 63 cents: 2 Q, 1 D, 3 P

Statistical Functions Sum, Average, Max, Min, Count –Ignore text and logical values. Can have many arguments: =SUM(A1:A3, 12, B3:B7)

Examples of Using Statistical Functions Compute each student’s: Best score, Lowest score, exam average Average of the best 3 scores Average of the best 2 scores

Large(Data range, kth value) Returns the k-th largest value in a range. Average of the best two exams: –=(Large(B2:E2,1) + Large(B2:E2,2))/2

Average Excluding the Highest and the lowest Scores

Text Functions Lower(text): Lower(“David”) -> “david” Upper(text): Upper(“David”) -> “DAVID” Proper(text): The first letter in each word in uppercase and other in lower case

Date & Time Functions How Excel handles dates: –Serial #: 1/1/1900 – day 1 Functions: –Today() – today’s date –Now() – current date and time –Year(a date) –Month(a date) –Weekday(a date)

Examples Tomorrow’s date? How many days to July 4 th ? Compute the age given a date of birth.

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 <= % tax < taxable income <= % tax Taxable income > % 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 = per additional unit

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

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

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

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 <>

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), (100 < KH <= 300), 30 cents per KH –All KH over 300, 40 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 = per additional unit. –Non residents: Total units taken <= 9, tuition = 3000 Total units taken > 9, tuition = per additional unit.

Resident or Not Units <= 12 or Not Units <= 9 or Not