Spreadsheets17 February 2011

Basic StructureSpreadsheet (Worksheet)

cell (letter-number)

Column (letters)

Row (numbers)

workbook = collection of worksheets

What Can Be In a Cell

Label – identification for people Constant – any format

› Text, number, picture, hyperlink, …› Value for computer› Format for people

Formula – uses cells & constants› Always begin with =

Simplest Formula

=cell Why do you use it? Fundamental Principle:

› Never have to change anything in two places

› Sound familiar? Copy-paste

› Fine if you really want a snapshot

Formulas Referencing Cells

Once you define the formula› Can change the values as often as you like› Automatically re-computes

Treats cells as variables› Defined by location, not value› Each cell constant or another formula

Example› Pay = hourly rate * hours worked

Values can change Formula remains the same

Formulas Using Constants

Use constants when they will not change

Values that won’t change:› Computing the area of a circle

Π r2

› Computing the area of a triangle ½ base*height

What about…› Minutes in an hour› Days in the year

Formulas Operations

› Simple math operators› Functions

Values› Constants› Cell selection

Typing Selecting

Cells must have appropriate values› e.g., not text for math function

Exercise

Want to compute 250x²-10y²

√ 100 (5x-y)for any x and y

_______

Data Types

Numbers Dates Boolean (true or false) Strings [error values]

Single values Arrays Tables

Some Commonly Used Functions

Statistical and mathematical› sum, average› minimum, maximum › floor, ceiling, round

Selective› counts› if

Formatting

Copying formulas Want the same information for different data

› Example: min, max, avg grades for each assignment

Can use copy or fill Copying a formula moves it relatively

What if I Want the SAME Place

Absolute positioning› Can lock the cell, column or row

Cell: $A$1 Column: $A1 Row: A$1

› To change a reference to absolute Insert $ Use F4

Exercise

Start withA1 hourly rateB2:B8 dateC2:C8 hours worked

You are to add D2:D8 day’s pay

Only want to type the formula ONCE

Using Multiple Worksheets

Why?› Separate input data› Presentation› Summarization› Versions

How to reference between› Sheet!Cell

To go between workbooks› ‘[workbook]worksheet’!cell

Exercise

From prior exerciseMove hourly rate to another sheet

Why Multiple Sheets?

General structure› Data on one page› Computations on another

Easy to change the data

Referencing Multiple Cells

Continuous cells (RANGE)› Colon (:)› Drag cursor

Combining (UNION)› Comma (,)

Naming sections

Under Formulas tab,› Name Manager: Define Name

Some default options› If the row or column has a label, will use it

Can collect non-adjacent Absolute addresses

What else can you Name?

Constants Single Cells Formulas

Why name?

Human readability Convenience if the section size

changes

Operator Precedence

Symbol Operator Order of Precedence

Colon (:) Range 1st

A space Intersection 2nd

Comma (,) Union 3rd

- Negation 4th

% Percent 5th

^ Exponentiation 6th

* and / Multiplication and division 7th

+ and - Addition and subtraction 8th

& Text concatenation 9th

=, <, >, <=, >=, and <> Comparison 10th

Built-in Functions

Lots of them! Explore! Wizards

Complex Computations

Option 1› Separate entries and hide fields › Hide columns or use separate

spreadsheets Option 2

› Build them up in pieces› Use parentheses if you can’t remember

precedence Option1, followed by option 2