CS&E 1111 ExLogic Microsoft Excel Logical Functions Objectives: Using Boolean Logic in Spreadsheets l Relational operators l Boolean operators –Functions l None of logical construct l Using Conditional Formatting

CS&E 1111 ExLogic Boolean Logical Values Is 3 greater than 5 ? The answer is either True or False TRUE and FALSE are Boolean Values Mathematically this would be represented by the expression 3>5 How much greater is 5 than 3? This answer requires an arithmetic value Mathematically this would be represented by the expression 5 - 3

CS&E 1111 ExLogic, =, =, <> l The result is always either TRUE or FALSE l Relational Expressions: =38<=6 results is the value FALSE =B2=5+3 results is the value TRUE if B2 equals 8 Excel provides a class of operators known as Relational Operators that can be used to perform a comparison of the left and right sides of an expression

CS&E 1111 ExLogic Blue’s total is higher than Jones’ grade: =E4>E5 Jones’ total is the maximum in the class: =E8=E5 The average total of students is less than 300: =Average(E4:E6)<300 Simple Relational Expressions

CS&E 1111 ExLogic Are these expressions equivalent? Precedence of Relational Operators =B4+B5<=150 =(B4+B5)<=150 Relational operators are always evaluated last…

CS&E 1111 ExLogic How do you determine if all of the students got above 320 points to pass the class or if anyone got below 320 points? Boolean Logic Operators We can use Boolean Operators - each operator has a corresponding Excel Function AND, OR, NOT

CS&E 1111 ExLogic Boolean Logic Operators l AND - All items must be true for the statement to be true l OR - At least one item must be true for the statement to be true l NOT – switches a True to a False and a False to a True

CS&E 1111 ExLogic The AND Function Excel uses a Function to perform the AND operation Syntax: =AND(logical1,logical2,...) Returns TRUE if all its arguments are TRUE; returns FALSE if one or more arguments is FALSE =AND(TRUE, TRUE)  TRUE =AND(F5,F6) where cell F5=TRUE & cell F6= TRUE  TRUE =AND(F5:F10) where cell F10=FALSE  FALSE =AND(3>B7, 2+4=5) equals the value FALSE where cell B7=1 For more details on how it treats text or blanks, look at the function on Excel help.

CS&E 1111 ExLogic The AND Function Is everyone in the class an Honors student? =And(F4:F6) Did everyone pass the course? - the passing score is 320 points = And(E4>=320, E5>=320, E6>=320)

CS&E 1111 ExLogic The OR Function Excel uses a Function to perform the OR operation Syntax: =AND(logical1,logical2,...) Returns TRUE if any of its arguments are TRUE; returns FALSE only if all arguments are FALSE =OR(TRUE, FALSE)  TRUE =OR(F5,F6) where cell F5=FALSE & cell F6= FALSE  FALSE =AND(F5:F10) where cell F10=TRUE  TRUE =AND(3>B7, 2+4=5) equals the value TRUE where cell B7=1 For more details on how it treats text or blanks, look at the function on Excel help.

CS&E 1111 ExLogic The OR Function Is anyone in the class an Honors student? =OR(F4:F6) Did at least one student pass the course - the passing score is 320 points = OR(E4>=320, E5>=320, E6>=320) Can we just write OR(E4:E6>=20)?

CS&E 1111 ExLogic The NOT Function Excel uses a Function to perform the NOT operation Syntax: =NOT(logical) Reverses the value of its argument. Turns a TRUE to a FALSE - and a FALSE to a TRUE. Use NOT when you want to make sure a value is not equal to one particular value. A NOT function takes only ONE argument =NOT(FALSE) equals the value TRUE =NOT(F3) where F3=True equals the value FALSE =NOT(3>5) equals TRUE

CS&E 1111 ExLogic The NOT Function Blue is not an Honors student =NOT(F4) Blue didn’t get a passing grade (320)? =NOT(E4>=320) is the same as E4<320

CS&E 1111 ExLogic How can we determine if none of the students are Honors students? Prove at least one student is an honors student (TRUE) then you know the statement none is FALSE = NOT(OR(F4:F6)) Another way is to prove each one is not an honor’s student = AND(NOT(F4), Not(F5), Not(F6))

CS&E 1111 ExLogic More Practice Blue’s total and Jones’ total are greater than Grey’s: =AND(E4>E6, E5>E6)  FALSE Grey’s total is not the maximum grade: =NOT(E6=MAX(E4:E7))  TRUE None of the students passed the course = NOT(OR(G4:G5))  TRUE

CS&E 1111 ExLogic “Conditional Formatting” allows the user to format a cell or range of cells based on specific criteria. The user has the option to setup criteria based on a value in a cell or based on a formula. Conditional Formatting

CS&E 1111 ExLogic What we’ve learned using Boolean Logical Constructs in Decision Making l A relational expression can be used to compare two values. l To determine if a list of logical arguments are ALL true use the AND function. (every, both) l To determine if at least one value is TRUE from a list of logical arguments use the OR function. (any, some) l Use the NOT function to change a TRUE value to FALSE and visa versa. Combine a NOT(OR() construct to determine if none of the values are TRUE.