IENG 423 Design of Decision Support Systems Modeling with Excel Excel Basics More on Functions, trouble shooting formulas

MS Excel Categories of Functions in Excel Math & Trig Statistical Time/Date Text Financial Logical Lookup Custom

MS Excel Common Functions Math & Trig ROUND(number, ndigits) Ceiling(number, significance)  Rounds up to multiples of significance Floor(number, significance)  Rounds down to multiples of significance LOG(number, base)  Returns a logarithm of number to a base base

MS Excel Common Functions Math & Trig RAND()  Returns a uniform random number between 0.0 and 1.0  ROMAN(number) Converts an arabic number to a Roman numeral SUM(number,number…)  Calculates the sum of a set of numbers, range SUMIF(criteriaRange, criteria, sumRange)  Calcs sum of range if criteria =true in criteria range SQRT(number)  Calcs the square root of number

MS Excel Common Functions Statistical AVERAGE(range)  Returns the arithmetic mean of range COUNT(range)  Returns the number of cells in range containing numbers FORECAST(x, known_ys, known_xs)  Returns linear project of x bases linear model using known xs and known ys TREND(knownys, knownx, newxs, const)  Returns predicted new y values based on linear least squares model

MS Excel Common Functions Statistical MAX(range)  Returns the largest value in range MIN(range)  Returns smallest value in range MODE(range)  Returns most frequently occurring value in range MEDIAN(range)  Returns middle most value in a set of values (range) RANK(number, range, order)  Returns the relative rank of number from a set (in range), either ascending or descending (order)

MS Excel Common Functions Date/Time NOW()  Returns current date and time (from computer’s clock) TODAY()  Returns current date formatted as a date

MS Excel Common Functions Financial DB(cost, salvage, life, period, month)  Returns the depreciated value of assets for a specified period of time PMT(rate, nper, present_value, future_value, type  Calculates payments for a loan due at begin or end of period (type), at a fixed RATE, for fixed number of payments (nper), based on the principal (present_value) and a desired future value NPV(rate, payment,payment,…)  Calculates the net present value of an investment by using a discount rate and a series of future payments (negative values) and income (positive values).

MS Excel Common Functions Logical IF(log_test, true_action, false_action)  Take different action depending on whether the log_test is true or false AND(log_test1, log_test2,…)  Returns true only if all log_tests are true OR(log_test1, log_test2,…)  Returns True if any log_test is true NOT(log_value)  Makes true false and false true

MS Excel Common Functions Text functions CONCATENATE(text1, text2,…)  Returns a single text string made of arguments LEFT(text, n)  Returns the left n characters of text RIGHT(text, n)  Returns the right n characters of text MID(text, start, n)  Returns a subset of the string text, beginning at start for n characters SEARCH(look_for, in_text, start)  Searches for string (look_for) in a string (in_text) starting at start – returns the character position number in in_text

MS Excel Errors Error codeProbable Problem #####Cell too small for value #VALUE!Something wrong with the input to a formula, probably the wrong type #NAME?The formula contains something that Excel does not recognize, typo? #REF!Formula makes a reference to a cell that does not exist #DIV/0!Can’t divide by zero

MS Excel – Trouble Shooting Errors Tracing Precedents What cells is a formula using? Tracing Dependencies What formulas are using this cell? Watch windows