SPREADSHEETS Define/Uses Software primarily used for business and scientific data analysis. The advantage of using a spreadsheet is in its speed at which an analysis can be done. (Great for repetitive calculations and answering “What if” questions.) Main components Menus Toolbars Workbook/Worksheets Individual Cell

SPREADSHEETS (Worksheets) Cells May hold text, numbers, and formulas. Referenced by column and row index (letters and numbers, respectively) (e.g. A1, C6, etc.) Selection of multiple cells. Numerous possibilities for formatting using menus or toolbars. Font, color, border, width/height Worksheet layout Column headings/labels Merge cells for text Separate worksheets for new data.

SPREADSHEETS (References) Cell References (also called “Range”) May apply to one or multiple cells. Continuous (adjacent) cells are referenced with a colon (e.g. A5:A9) Multiple references to single cells are referenced with a comma. (e.g. A5:A9,C13:D13) Examples One cell…A2 Five cells… A5,A6,A7,A8,A9 or A5:A9 C3:D9 B13:D13 Entire column F:F

SPREADSHEETS (Named Ranges) Named Range Any single cell or group of cells may be assigned a name. Named ranges are used in formulas (more later). Makes the spreadsheet more “readable”. Example Consider a spreadsheet with a few test scores. The range of cells holding the scores is assigned the name “Scores”. This can later be used in any formula to refer to this specific range. There are two ways to name a range in Excel. 1.) Select the range and then use the name box 2.) Use the menu sequence Insert-Name-Define Names should be intuitive words or abbreviations. Best to use letters and numbers. No spaces or symbols other than the underscore.

SPREADSHEETS (Formulas) Formulas Entered directly in the cell of interest. Displayed in cell and formula bar. Must begin with ‘=‘ or ‘+’, although I highly recommend using ‘=‘ May contain combination of numbers, mathematical operators, functions, and worksheet ranges (named or not). May be designed such that they can be copied to other cells and still yield desired result. Examples “=4+2*3*(4+6) - 3*2+5”(watch operator precedence …result here is 63) “=A1+B5*7”(using relative cell references) “=$A$1 + $B$5*7” (Using absolute cell references) Common Errors Divide by zero (#DIV/0!) Circular reference (including a reference to the cell containing the formula within the formula.) Insufficient column width (#####) Using text when Excel expected numbers (#VALUE) Using wrong/misspelled named range (#NAME)

SPREADSHEETS (Formulas) Absolute References Using a dollar sign ‘$’ before the column or row index in a cell reference (e.g.’s $A2, $A$2, $B$5:$C2) Cell references that always refer to cells in a specific location. If a dollar sign precedes the column or row index, such as $A$1, the column and/or row reference is absolute. Absolute references do not adjust when you copy them to another cell Named ranges are absolute references Relative References Created by omission of the ‘$’ (e.g. A1) Reference is relative to original and destination cells when a formula is copied. Original formula in red was copied to other cell locations. (cell C10) Absolute references do not change. Relative references increase or decrease accordingly. #REF errors due to negative cell references.

SPREADSHEETS (Formulas) Example Original formula in red (cell G10) was copied to cells C5, E12, J2, and J15 References errors due to zero or negative column and row indices Absolute references do not change.

SPREADSHEETS (Formulas) Example Calculate the circumference of a several circles by entering one formula and then copying and pasting the formula to adjacent cells. Absolute reference is to the row index only although it could have also been used with the column index Formula entered in cell B2 then copied to cells B3:B6

SPREADSHEETS (Functions) Excel’s Built-In Functions Excel comes with numerous functions that allow you to simplify your formulas and spreadsheets. Examples: SUM() AVERAGE() MIN() MAX() and dozens more. List of available functions can be viewed with the function wizard Examples =A1+A2+A3+A4+A5+A6+A7+A8+A9+A10 versus =SUM(A1:A10)

How Functions Work =SUM(A2:A10) Function SUM(Cell Values passed from formula) Program code to add all numbers passed to the function. Result=A2+A3+A4+A5+A6+A7+A8+A9+A10 Return Result End Function Result will be displayed Cell A11 Function Wizard Formula Bar SPREADSHEETS (Functions)

SPREADSHEETS (Functions) Excel’s Built-In Functions Most (but not all) functions require you to pass at least one value. Some functions may require values to be passed in a specific order. Parentheses are required with all functions and are used to enclose values to be passed. Values may be passed as numbers, text, or cell references. Functions usually (but not always) return ONE value. Functions can be embedded in any formula. (e.g. =AVERAGE(A1:A10)+1.2*STDEVP(A1:A10) Use function wizard or on-line help for syntax requirements.