Understanding spreadsheets
A spreadsheet is a computer program that does calculations on figures in rows and columns.
| Rows go across |
Columns go up and down:
| The basic screen design of a spreadsheet is a table of rows and columns.The oblongs made by the intersections of the rows and columns are called cells.Each of these cells has a name (address) that is made by putting the name of the column with the name of the row.Cell B3 is the cell at the intersection of column B and row 3. |
Cells are labelled:
|
A1 | B1 |
| A2 | B2 | |
| A3 | B3 |
<!–
A cell can contain:
- a title (like “Age Groups” in cell A1 of the second table below) or:a number (like “109″ in cell B2 of the second table below) or:a formula (like “B2+B3+B4+B5″ in cell B6 of the second table below)
here–>
| A table can be created in any size. This table has six rows, three columns and eighteen cells.We can fill in some of the cells with formulas that use the cell addresses of figures in other cells. If we alter the figures, the formulas will recalculate the results for us. | A1 | B1 | C1 |
|---|---|---|---|
| A2 | B2 | C2 | |
| A3 | B3 | C3 | |
| A4 | B4 | C4 | |
| A5 | B5 | C5 | |
| A6 | B6 | C6 |
| We can use a cell to enter: a title (see green cells), a number (see blue cells) or a formula(see yellow cells)We can then alter the numbers whenever we like, and recalculate. The formula will automatically calculate the totals and percentages. | Age Groups | Numbers | Percentages |
|---|---|---|---|
| 15 to 29 | 109 | (B2/B6) x 100 | |
| 30 to 44 | 218 | (B3/B6) x 100 | |
| 45 to 59 | 242 | (B4/B6) x 100 | |
| 60 to 74 | 46 | (B5/B6) x 100 | |
| Total | B2+B3+B4+B5 | C2+C3+C4+C5 |
| Here the spreadsheet has calculated the results for the numbers we have entered above. If we entered new numbers, the spreadsheet would calculate new results. | Age Groups | Numbers | Percentages |
|---|---|---|---|
| 15 to 29 | 109 | 18 | |
| 30 to 44 | 218 | 35 | |
| 45 to 59 | 242 | 40 | |
| 60 to 74 | 46 | 7 | |
| Total | 615 | 100 |
Percentages The formula for a percentage is:
number divided by total, all multiplied by one hundred If you look at the above diagrams you will see how a formula is entered in a cell to calculate this in a spreadsheet. The formula (B2/B6)/100 in the example will work perfectly well But, if you copy it to other cells you need to mark the cell reference for the total (B in this example) so that it does not alter when you copy it. In Excel spreadsheets this is done by putting a $ before the letter and number of the cell reference you want to stay the same. So the formula becomes: (B2/$B$6)/100
As well as the specialist spreadsheet programs that do this, wordprocessors often include a simple spreadsheet as a tool. In WordPerfect 5.1 and Wordperfect for Windows it is an aspect of tables. This is very useful if you need to include a table of figures in an essay.
| External link to a site where you can try these ideas out and find out much more: “Wt is a spreadsheet? on MathsNet |
Notes on the Excel spreadsheet
- clicking on the grey button at the top of a column highlights the whole column
- clicking on the grey button at the left of a row highlightsthe whole row
- clicking on a cell gives it a black border. This means that the cell is active– which means you can enter things in it from the keyboard.
- You can enter words or numbers
- If you enter words as headings, they will appear to stretch across several cells. You can adjust the row or column to fit by using the formatmenu or by mouse movements between the grey cells at the top or left side.
- If you laid out a spreadsheet with headings down the side and headings across the top – ready to enter data – you could call that a template
- When you create a template, or enter data, you should name your spreadsheet by saving it to your disk. Simple eight letter names are best for computer files. So, if your spreadsheet shows crime statistics for 1981 and 1994 you could save it as crime8194
— original source http://studymore.org.uk —
