The Spreadsheet Manual
Contents
The Psion Pocket Spreadsheet can be thought of as a electronic sheet of paper. This sheet is divided into a grid of boxes, rather like a sheet of graph paper.
This simple arrangement, when transformed by the processing power of the Organiser, forms perhaps the most versatile and powerful tool you can add to your computer.
The information produced on your Pocket Spreadsheet as not just for you alone; it can be shared with colleagues. Worksheets produced on the Organiser can be transferred to a desktop computer to run in Lotus 1-2-3 or Symphony, and worksheets prepared in Lotus 1-2-3 or Symphony (or any other spreadsheets which accept DIF extension files) can be transferred just as easily to the Organiser.
The Pocket Spreadsheet gives you the power and flexibility of spreadsheets costing many times as much, together with the portability and ease of use of a pocket calculator.
The Psion Pocket Spreadsheet does not run on the Psion Organiser Model CM.
In the same box as this manual is a program pack. Its external appearance is identical to that of Datapaks, which are discussed in the Organiser manual. To insert the pack:
- Remove a Datapak or a cover by pulling on the ribbed outer section of the pack.
- Push the program pack into the empty slot until it clicks home.
The program pack may be used in either of the side slots.
The Psion Pocket Spreadsheet requires around 8K of memory, but if large worksheets are to be used then more free memory will be required.
To run the Spreadsheet:
- Press the ON/CLEAR key to switch on your Organiser.
- If necessary, press the ON/CLEAR key to make the top-level menu appear.
- Press the ON/CLEAR key once more. The item Plan will have automatically been added to the end of the top-level menu.
- Select Plan from the main menu in the usual way by moving the cursor to that item with the cursor keys, or by pressing P until it is flashing on Plan, and then pressing EXE.
Straight away you will see the top left corner of the grid. The tutorial chapters which form Part One explain where to go from here. However, if you are already familiar with spreadsheets, you can go straight to the reference chapters, which contain a summary of the particular features of the Psion Pocket Spreadsheet.
Part One: Tutorial
A Spreadsheet is an electronic version of the accountant's pad. The pad is divided into rows and columns in the form of a grid, labelled across the top with letters and down the left hand side with numbers.
On the Pocket Spreadsheet, the grid goes from column A across to column Z and from row 1 down to row 99. Only a number of these can be shown on the screen at any one time, but you can move around the grid to view any part of it. So imagine that the screen is like a window in a piece of card which you move up, down, left or right to see different areas of the grid. Each of the boxes in the grid is called a cell.
The cell which you are in at any given moment is the current cell.
To keep track of which cell is current, we use a cell reference like a grid reference on a map. The cell reference is made up of:
- The letter of the column
- The number of the row
When you start up the Spreadsheet, you enter the grid at the top left corner. The current cell is marked by a cursor bar:
| | | B2 | | B | |C | | | |||
| | | 2 | | _ | | | | or | | B2 | | B | |C | |
| | | 3 | | | | | | | 2 | | _ | | | | |
| | | 4 | | | | | |
To start with you are in cell B2. Cells are separated by dotted bars. The current cell reference is always shown in the top left cell in the display so that you know exactly where you are on the grid:
| | | B2 | |B | | C | | | |||
| | | 2 | | | | | or | | B2 | |B | | C | | |
| | | 3 | | | | | | | 2 | | | | | | |
| | | 4 | | | | | |
The contents of cell A1 are then hidden; this is why you don't see A1 in this cell. The cells in the top row and leftmost column are title cells. They contain titles:
| | | B2 | |B | | C | | | |||
| | | 2 | | | | | or | | B2 | |B | | C | | |
| | | 3 | | | | | | | 2 | | | | | | |
| | | 4 | | | | | |
The letters/numbers they show to begin with are just start-up values, so you can change them later to titles of your choice.
Press the <right> cursor key once and the display looks like this:
|C2 |B |C | |2 | |_ | or |B2 |B |C | |3 | | | |2 | |_ | |4 | | |
The cursor has moved to the right and cell C2 is now the current cell, as shown by the cell reference at the left of the top line.
Press <right> again and the screen scrolls one cell to the left, so that the new current cell (D2) comes onto the screen, on the right. The current cell reference is always displayed in the top left corner whatever you do.
- Press <right> and <down> a few times and watch the cell reference change as you go across and down the grid.
Now use the <up> and <left> cursor keys to return to the cell where you started from, B2, so that you can start entering data into the Spreadsheet.
When you enter the Spreadsheet, the keyboard is in numeric mode by default. This means that you can type in numbers directly but have to keep the SHIFT key pressed if you want to type in text.
- To switch the keyboard to alpha (text) mode hold down SHIFT and press NUM. Do this again to return to numeric mode.
When you are in numeric mode, the cursor appears as a bar; in text mode the cursor appears as a flashing block.
- In cell B2, type: 44
As soon as you start to type the number, the rest of the line to the right of the cursor is cleared to accept your input.
- Press EXE to enter the number.
The full display is restored. 44 moves to the right of the cell; this is the way numbers are displayed.
- Press the <up> key to move down to cell B3 and type: 53 EXE
- Move to cell C3. Press SHIFT and NUM together to set the keyboard to alpha mode and type: sum EXE
You can type this in lower or upper case, whichever you wish. To change between upper and lower case press SHIFT and <up> together.
When you press EXE, sum appears in the current cell. Because it is text rather than a number, sum is aligned left, not right, when accepted.
- Experiment with typing in some more numbers and text. in lower and upper case, to get used to the keys and to moving around the grid.
If you try to enter numbers followed by letters, e.g. 231 lbs. in a single cell, you get an error. This is because the Spreadsheet cannot accept this as a number. If you enter letters followed by numbers, e.g. NO.23, this will be accepted; the numbers are taken as a sort of text.
Alternatives while entering data
- Pressing one of the cursor keys without first pressing EXE moves you to the adjacent cell in the relevant direction, entering your data in the process. This is a timesaver, since you don't have to press EXE, wait for it to finish and then press a cursor key to move to the next cell.
- Press MODE whilst entering data. You can then use the cursor keys to move to any point in the data so far entered to edit it. Press MODE again to return to the usual function of cursor keys.
Deleting
- To correct a mistake whilst you're typing in, use DEL to delete the character to the left of the cursor and SHIFT-DEL to delete the character which the cursor is highlighting.
- To delete the entire contents of a cell just move to that cell with the cursor keys and press DEL once. Alternatively, move to the cell and type in new contents. The old contents aren't actually replaced by what you've typed until you press EXE; if you press ON/CLEAR twice instead of EXE the original contents are restored.
Numbers always appear at the right of the cell (‘ranged right’); text appears to the left of the cell ('ranged left'). The default column titles (A, B, C...) appear ranged left, but so do the row numbers (1, 2, 3 ... ) because these are a special case and are treated like text.
You are allowed to enter numbers or text in any of the title cells, too.
Go to cell B1 and enter the title TOTAL. Run down column B. The title is shown even when cell B1 has scrolled off the screen.
Note that, if you enter text which has trailing spaces, these are discarded by the Spreadsheet when you press EXE. Text which has leading spaces will be left as entered, however. This allows you to centre text for use as headers and so on.
If you want to clear what you've done completely and start afresh, press MODE EXE then Z then Y. (This procedure is explained later; at the moment use it whenever you want to start afresh.)
Now you can add together the numbers entered with a formula. If you've changed the numbers in the top left corner of the grid, re-enter them so your grid looks like this:
| |total|C | |2 | 44| | |3 | 53| sum| |4 | | |
Formulae are typed into cells in just the same way as numbers and text, but when evaluated by the Spreadsheet their results are displayed, not the formulae themselves.
- Use the cursor keys to move to cell B4 and type: =B2+B3 EXE
Whether you type in upper or lower case does not matter.
This is a formula which says: 'make the contents of the current cell (B4) become equal to the contents of cell B2 plus the contents of cell B3'. When you press EXE formula is evaluated and the display looks something like this:
|B4 |total |C | |4 |_ 97| | or |B4 |total|C | |5 | | | |4 |_ 97| | |6 | | |
The formula =B2+B3 is not visible at the moment. It is still stored in memory, but only the value it produces is displayed. The Pocket Spreadsheet contains commands to display and edit the formulae in the grid; but, because the formulae used in these first examples are quite straightforward, they can for the moment be left out of sight.
The formulae you choose to enter into cells in the Spreadsheet might be very complex. But the principle by which a result is calculated in one cell by referring to data stored in other cells would be the same as in a simple example. A basic operation you would use is to change the entry in one cell and see how it effects the result in another cell. For example
- Go to cell B2 and type: 121 EXE
- Look at cell B4. The new result is displayed.
In effect, what you have done is to program the Organiser without using any conventional programming language. In this case you have created a worksheet which will add any two numbers and display the result; but you could have chosen a more complex mathematical function with more than two variables.
In the next example, the result of one sum is ‘called’ in order to work out the result of another.
Say we wanted to work out the amount of free cash left over for the month after paying the bills. First:
- Clear the grid by pressing MODE EXE Z Y.
- Go to each cell in this list and enter the text shown alongside:
A2 SAL
A3 GAS
A4 ELEC
A5 FOOD
A6 MORT
A7 CAR
These are your titles.
- Enter these figures in the stated cells:
B2 850
B3 40
B4 30
B5 100
B6 420
B7 90
- Go to cell C2 and type: =B2-B3-B4-B5-B6-B7 EXE
When you press EXE the values for all of the bills are deducted from the monthly salary and the result, the amount of free cash left over for the month, is inserted in cell C2. C2 should show 170.
But suppose we first have to calculate the car bill each month, from the amount spent on petrol, maintenance and paying back an original loan.
- Enter the following text and numbers in these cells:
C7 FUEL
C8 MAIN
C9 LOAN
D7 50
D8 20
D9 30
- Go back to cell B7. Type =D7+D8+D9 EXE.
The completed worksheet will now look like this:
|SAL |BILLS|C |D | |GAS | 850| 160| | |ELEC| 40| | | |FOOD| 30| | | |MORT| 100| | | |CAR | 100|FUEL | 50| |8 | |MAIN | 20| |9 | |LOAN | 30|
Cell B7 displays the result of the calculation of the car bill, but at the same time this is just a number in the calculation of the amount of free cash left at the end of the month.
- Change the number in D7, the fuel bill, to 60 then go to C2 to see how the total has changed.
This is an important characteristic of Spreadsheet cells: they can be both the end result of a calculation at one level and just one of many items in another calculation at a higher level.
In a real worksheet you might have several such levels, and in constructing the sheet it may be helpful to think of the calculation as broken down into a series of smaller calculations adding together to give the end result.
(NB: In the above example, you could change the number in cell B7, the car bill, and see the change registered in the result cell C2. But by changing the entry in cell B7 you would have deleted the formula which connected the sum of FUEL, MAIN and LOAN with the calculation of the cash left over at the end of the month. To reinstate the connection you would have to re-enter the formula.)
Just as the Organiser's Prog option has a menu, the Spreadsheet has its menu, containing various commands. You are not presented with this menu immediately you enter the Spreadsheet, but can reach It by pressing MODE whilst you are viewing the grid.
10.30 Grid File Goto or GRID FILE GOTO Edit Info Titles EDIT INFO TITLES Quit QUIT
These options are not all the same kind of command:
Grid and File lead to separate sub-menus. These will be dealt with in the next chapter.
Goto, Edit, Info and Titles enable you to change how you view the grid, and help alter its contents. These are the subject of this chapter.
| Copy | Copies the contents of one range of cells to another range. |
| Delete | Deletes the contents of a range of cells. |
| Zap | Clears all data from the grid. |
| Format | Sets the numeric display format of a range of cells. |
| Widths | Sets the column width for a range of cells. |
| Prints out the values of a range of cells. | |
| Recalc | Sets the formula recalculation mode. |
This Chapter uses a worked example to familiarise you with the uses of these menu items. If you want to leave the example temporarily, just press ON/CLEAR to return to the top-level menu. When you select Plan again you return to where you left off.
Zap - clearing the grid
To start our new example the grid must be cleared. Last time you used the Quit command. Zap is the same as Quit except that it returns you to the empty grid, not to the Organiser top-level menu.
From the grid:
- Press MODE.
- Select Grid from the Spreadsheet menu, then select Zap from the Grid menu.
If you have entered data since last quitting the worksheet you will be asked to confirm the command. Pressing N returns you to the Grid menu.
- Press Y. You return to an emptied worksheet with its default display settings:
|B4 |B |C | |2 | | | or |B4 |B |C | |3 | | | |2 | | | |4 | | |
Example - using Widths, Format and Copy
Set up the following table to work out the value of a portfolio of shares from the day's price-per-share. The value of each group of shares will be calculated and displayed in the sub-total column, and this column will be added and the overall total displayed in cell E3.
| |QTY |TODAY|SUB-T|TOTAL|F |PORT| | | | | |BT | 1000| 2.37| | | |TSB | 500| 0.9| | | |GAS | 200| 0.75| | | |BA | 200| 1.1| | |
- In cell E3 enter the formula: =D3+D4+D5+D6.
For the moment-the result will of course show as zero, since the cells in column D are empty.
Before entering further data it is necessary to prepare the grid.
Widths
At the moment, the columns on your grid are each 7 characters wide on model L4 or 5 characters wide on model XP (apart from the first column, which is narrower). What if the total value of your portfolio was more than 9999.99, say? Your worksheet couldn't currently display any amount greater than this.
Assuming that the total might reach 10000.00, we need to have column E 8 characters wide. if the total was 12950.00 and the cell was only 7 characters wide, the result would show only as '#######'.
To change the column width:
- Press MODE, and select Grid.
- In the Grid menu select Widths. The bottom line of the display shows: Widths E:E with a cursor flashing on the first E (or whatever the letter is of the column you were in).
You are being prompted to select a range of columns whose width you wish to change. If we wanted to set columns C, D and E we would want to change E:E to C:E. You can do this in two ways.
- Experiment with both methods:
(a) Type in C: E - the suggested range disappears as soon as you press C. Pressing ON/CLEAR clears the line and pressing ON/CLEAR again restores the suggested range. Press EXE to enter the range. The display then suggests a width to which to set the chosen columns. You have a choice:
- To accept the suggested width press EXE.
- To change the width, type in the new one. Use DEL to correct if necessary. Press ON/CLEAR to clear what you've typed. (Pressing ON/CLEAR again returns you to the Grid menu.) Press EXE to enter the width.
(b) Use <left> and <right> to move across the cells just as if you were scanning across the grid in the usual way. Continue pressing the cursor keys until the letter to the left of the colon is that of the leftmost column you wish to effect - C. Then press MODE and use the cursor keys again to change the letter to the right of the colon to that of the rightmost column you wish to effect - E.
If you then want to go back and correct the left hand letter press MODE and then the cursor keys again. Pressing ON/CLEAR moves you back to E:E, or whatever column you were in when you selected Widths. Press EXE to enter the range. The display then prompts as above for the width to which to set the chosen columns.
The maximum width is 12 characters.
- For our example set D:E to 8 characters wide.
- Then select Widths a second time and set B: C to 5 characters wide.
Format
The figures in the portfolio table are monetary, so we need to set the numbers in the relevant columns to appear with two decimal places: 0.90, 1.10.
- Go to the Spreadsheet menu and select Grid.
- From the Grid menu select Format. A sub-menu is presented, offering you a choice of the types of cells you wish to effect:
- Cells affects only a certain area of cells, which you specify. In this area, or 'range', only cells which have contents are affected. (If there are some empty cells in this range and you later enter data into them, the data will be displayed with the Spreadsheet's default format, not the one you selected.)
- Default sets all the empty cells in the grid, but none which have contents. Data later entered into the empty cells will be displayed with the selected format.
We want to set the format of the cells in columns C to E (TODAY, SUB-T and TOTAL). Some of these are empty so must be set with Default. Others already have contents, so must be set with cells. To set the format of the empty cells in column D:
- Select Default.
A menu is presented of types of numeric format:
General Integer
Fixed Scientific
These four types of format are defined in the Reference. For our example:
- Select Fixed.
You are asked for a number of decimal places. The suggested setting is 2, which is what we want for our monetary figures, so we don't need to alter it in the usual way - just:
- Press EXE to switch the suggested format on.
The cells in column D are now prepared to show sub-totals in monetary form.
Now to change the format of the cells in column C:
- Press MODE. Select Grid, then Format, then Cells.
As with the widths command, you are now prompted to define the range of cells you wish to effect. This time, though, the range asked for is not just a matter of columns, but also of rows.
Say you were in cell E3 when you selected Format. The bottom line of the display would then show:
Format E3:E3
with a cursor flashing on the first E on the lower line.
The area we need to select is the BT, TSB, GAS and BA cells in the TODAY column. That is, C3:C6 - which says 'C3 to C6’. This is a cell range. The figure below shows another range, C3:E6 - the rectangular area which has C3 and E6 as its top left and bottom right corners:
| B | C | D | E | F | |
| 2 | |||||
| 3 | |||||
| 4 | |||||
| 5 | |||||
| 6 | |||||
| 7 |
A cell range must be rectangular, but this could be a single row, a single column (as in our example) or a single cell. In the figure below there are three cell ranges: B2:B9, D2:G2 and D4:D4.
| B | C | D | E | F | G | H | |
| 2 | |||||||
| 3 | |||||||
| 4 | |||||||
| 5 | |||||||
| 6 | |||||||
| 7 | |||||||
| 8 | |||||||
| 9 | |||||||
| 10 |
Cell ranges are used in several of the Grid menu commands, so it is important to understand them.
To change the cell range you can use either of the methods you used to change the Widths range - i.e. either:
- Type in C3:C6 (or whatever range you want). Press ON/CLEAR to clear the line and ON/CLEAR again to restore the suggested range. Press EXE to enter the range.
- Or: Use the cursor keys and MODE to change each side of the colon. Note that you can now use <up> and <down> as well as <left> and <right> to change the number and letter parts of the cell reference. Press ON/CLEAR to return to the suggested range. Press EXE to enter the range.
- Experiment with the cursor keys and MODE to obtain different cell ranges.
When the range is C 3: C 6 press EXE.
The menu of types of numeric format is presented.
- Select Fixed. then 2 decimal places.
You are returned to the grid. Run down column C, TODAY, and see that the share prices are now in monetary form: 2.37, 0.90, 0.75, 1.10.
- Now set the format of cell E3 to 2 decimal places, so that the TOTAL will also display correctly. (Because it contained a formula, it wasn't affected by the Default format change.)
Copy
To work out the value of the BT shares in the sub-total column:
- Enter in cell D3 the formula =B 3 * C 3. Press EXE and the result, 2370.00, is displayed.
The sub-total for each of the other shares must be worked out using exactly the same kind of formula: =Bx*Cx where x is the number of the row.
To save typing in the formula four times over, copy the formula in cell D3 into cells D4, D5 and D6:
- Check that D3 is the current cell. Press MODE, select Grid and then select Copy from the Grid menu.
- You are asked to select a cell range to be the model to copy from. The suggested range is simply the cell that was current when you selected Copy - D3:D3. The range can be edited in the usual way, but for this example just press EXE.
- You are then asked to select the cell range to which the model cell(s) are to be copied. For this example the required range is D4:D6. Select this with the cursor keys and MODE or by typing it in, then press EXE.
You are returned to the finished worksheet, which should look like this:
| |QTY |TODAY|SUB-T |TOTAL |F |PORT| | | | | |BT | 1000| 2.37| 2370.00| 3190.00| |TSB | 500| 0.9| 450.00| | |GAS | 200| 0.75| 150.00| | |BA | 200| 1.1| 220.00| |
Relative and Absolute Cell References
This has completed the example worksheet. But to see how the Copy command works:
- Press MODE and select Info to show formulae.
- Run down the sub-total column and see what has been copied: =B3*C3, =B4*C4,=B5*C5, =B6*C6.
Why hasn't =B3*C3 been copied exactly into cells D4 to W.
If every character of the formula =B3*C3 had been copied exactly, it would have been an absolute cell reference.
A relative cell reference is one where only certain parts of the formula are copied exactly and others are modified In order to maintain the relationship which the original formula defined.
For example, you put the formula =B3*C3 into cell D3; i.e. the cell containing the formula was given the product of the contents of the two cells to Its left. When you copied this cell to the rest of the cells in that column, the same relationship was kept: all the cells display the product of the contents of the two cells to their left.
Or say a formula in cell X (below) contains a reference to the lightly shaded cell. If this formula is copied to cell Y it then refers to the heavily shaded cell. The two cells in each pair have the same relative positions.
| B | C | D | E | |
| 2 | ||||
| 3 | X | |||
| 4 | ||||
| 5 | Y | |||
| 6 |
By default the Spreadsheet assumes that cell references are relative.
To make a cell reference absolute:
- Prefix the letter and/or number part of the cell reference with a dollar sign, $.
For example, if a formula in cell E5 (Y in the example above) refers to $D$4 and you copy this formula to cell C3 (M that too will refer to cell D4, not to B2. (And if you copied cell C3, the reference to D4 would be copied ,again as being to D4.)
(Actually, when you copy a formula you don't create another modified formula in memory. All cells to which the formula has been copied share the same formula. The formula is stored only once, and contains a note of whether the cell references in it are absolute or relative.)
You can mix absolute and relative cell references within a single cell reference - for example $C3, C$3 (see Example 1).
There follow two further example worksheets. The first of these uses mixed cell references, the second some of the Spreadsheet functions listed in the Functions Reference.
Most of the processes involved in building a worksheet have been outlined in this chapter, but for further details of all the commands and settings see the reference section.
Commands which you might like to look up now are:
You will certainly need to be familiar with the last two commands when you start creating your own worksheets.
Example 1: Copying formulae containing mixed cell references
This worksheet calculates the prices of a number of commodities in five different currencies. Each day you can enter the exchange rate for the various currencies based on a standard currency, here the US dollar. Then you enter today's price of each of the commodities in dollars, then go to the appropriate cell to see the price of, for example, Silver in Yen.
This whole example can be built with just one formula which is copied to all the necessary cells: the price is multiplied by the exchange rate to give the price in the particular currency. The formula uses mixed cell references.
- Clear the grid with Zap.
- Set columns B to F to eight characters wide with Widths (from the Grid menu).
- Set all cells to 2 decimal places using Format then Default then Fixed (from the Grid menu).
- Enter these titles, exchange rates and commodity prices:
| |DOLLAR |STERLING|YEN |FRANC |DMARK | |RATE| | 0.64| 154.00| 6.11| 1.84| |GOLD| 406.25| | | | | |SILV| 5.47| | | | | |COPP| 484.37| | | | | |TIN | 1414.00| | | | |
- Now enter the formula =C$2*$B3 into cell C3 (Sterling. Gold). The result, 260.00, is displayed. The formula takes the exchange rate (in cell $2) from the top of the current column (cell C, not $C) and multiplies it by the commodity price (cell $13) at the left of the current row (cell 3, not $3).
- This formula is appropriate for all the price cells, so Copy the formula from C3: C3 to C3: F 6.
- When you press EXE a 'Busy...' message is displayed while all the various prices are calculated.
Then the worksheet should look like this:
| |DOLLAR |STERLING|YEN |FRANC |DMARK | |RATE| | 0.64| 154| 6.11| 1.84| |GOLD| 406.25| 260.00| 62563| 2482.19| 747.50| |SILV| 5.47| 3.50| 842| 33.42| 10.06| |COPP| 484.37| 310.00| 74593| 2959.50| 891.24| |TIN | 1414.00| 904.96| 217756| 8639.54| 2601.76|
The unnecessary decimals in the YEN column have been hidden. To do this:
- Select Format, then Cells. Select D2:D6 and then Integer.
This has completed the worksheet.
- Change the day's rates or prices and see the relevant change in the grid.
Recalc
But say you wanted to change all the day's exchange rates and commodity prices. Then the grid would spend time recalculating every time you press EXE (or an arrow key) to enter a new price or rate. Whereas the grid could calculate just once, after all the new data has been entered.
To do this, change the recalculation mode:
- Press MODE. Select Grid, then Recalc.
You are presented with a menu:
Manual Automatic
BY default the grid calculates automatically.
- Select Manual.
Now when you enter a formula, though it is evaluated immediately, any formulae in other cells referring to this cell are not recalculated. To make the whole grid recalculate, press EXE a further time.
Note: Whilst prices are displayed only to two decimal places, they may be entered to an accuracy of more than two decimal places. The precise figures you type am stored by the Spreadsheet and used in the calculations, then rounded up for display.
If you want to save this worksheet:
- Press MODE and select File. Select Save and give the worksheet a name. Press EXE. Enter a password if you wish and press EXE. This is explained fully on page 6-12.
Example 2: Using Spreadsheet functions
Two simple improvements could be made to the 'monthly bilIs' example by using Spreadsheet functions.
- Use the SUM function to add up the expenditures, instead of typing in the cell reference of each and every expense cell.
- Use the MONTH, YEAR and TODAY functions to display the current date at the top left of the grid.
Set up this table:
| |BILLS|REM|SAL |E | | | | 950| |MORT| 425| | | |FOOD| 200| | | |ELEC| 70| | | |CAR | 100| | | |7 | | | |
- In cell C2 enter the formula =D2-SUM(B3:B6).
The SUM function simply adds up the contents of the cells in the selected range (B3:C6). Quoting a cell range like this is obviously an advantage when you have a large number of cells to add up.
- In cell A2 enter the formula =MONTH(TODAY)+YEAR(TODAY)/100
This displays the current month number and year number, separated by a dot (provided you have set the time with the Time option from the top-level menu).
The formula uses 3 Spreadsheet functions:
The TODAY function returns the number of days elapsed today since 30.12.1899.
When this number is given to the MONTH function, MONTH returns the integer from 1 to 12 representing the month in which that day number lies.
Similarly, the YEAR function returns an integer from 0 to 178, representing the year after 1899 in which that day number lies.
In the formula, the number returned by YEAR is divided by 100 in order to make it .89 or whatever. Then when this is added to the result of MONTH, the month and year will be separated by the decimal point.
The finished worksheet looks something like this:
| |BILLS|REM|SAL |E |5.89| |155| 950| |MORT| 425| | | |FOOD| 200| | | |ELEC| 70| | | |CAR | 100| | | |7 | | | |
Two improvements to the date display
In May 1990, say, the date will show as 5.9, not 5.90. So use Format with Cells to make A2 to display to 2 decimal places.
When the year is after 2000, the YEAR function would mourn a value over 100. This, when divided by 100, would wrongly add 1 to the month number. To prevent this, change the formula in cell A2 to
=MONTH(TODAY)+MOD(YEAR(TODAY),100)/100
The MOD function divides the number returned by YEAR by 100 and then returns the remainder of this division. E.g. in 2012 YEAR returns 112, but MOD returns 12.
For a full explanation of these and all the other available Spreadsheet functions, see the Function reference.
Part Two, Reference
Functions
| ABS ACOS ASIN ATAN ATAN2 AVG CHOOSE COS COUNT DATE DAY ERR EXP FALSE FV |
HLOOKUP IF INT IRR ISERR ISNA LN LOG MAX MIN MOD MONTH NA NPV OPL |
PI PMT PV RAND ROUND SIN SQRT STD SUM TAN TODAY TRUE VAR VLOOKUP YEAR |
Functions
Any of the functions listed here may be included in cell formulae. A function takes the parameters supplied it and returns a value to the appropriate point in the formula.
Functions must be supplied with the correct number and type of arguments. If not, a 'syntax error' will be Indicated when you try to enter the formula into a cell.
The arguments must be enclosed in brackets and separated by commas.
Arguments may be literal values or expressions. In the descriptions of the functions:
<exp> is either a numeric expression or a reference to a cell displaying a numeric value (the numeric contents of the cell are taken for the operation).
<range> is a cell range in the format B2:G12.
<list> is a list of cell references, cell ranges and numeric expressions, separated by commas, for example B2, D3:F6,33.
Any other argument will be either a numeric expression or a reference to a single cell displaying a numeric value.
Example formulae using functions are:
- =AVG(B2:G17)
- =LOG(12)
- =LOG(B2)
The functions available in the Pocket Spreadsheet are these:
ABS(<exp>)
Returns the absolute value, i.e. without any sign, of <exp>.
For example, the formula =ABS(-10) returns the value 10.
ACOS(<exp>)
Returns the angle, in radians, whose cosine is <exp>.
ASIN(<exp>)
Returns the angle, in radians, whose sine is <exp>.
ATAN(<exp>)
Returns the angle, in radians, whose tangent is <exp>.
ATAN2(<exp1>,<exp2>)
Returns the angle, in radians, whose tangent is <exp2>/<exp1>.
Returns a result in the correct quadrant, taking account of the signs of <exp2> and <exp1>.
AVG(<list>)
Returns the arithmetic mean (average) of the values in <list>.
The items in <list> may be literal values, cell references or cell ranges. Specifically, function returns SUM(<list>)/(COUNT<list>)
CHOOSE(<exp>,<list>)
Returns the item at Position <exp> in the <list>.
The index, <exp> may be a literal value, a cell reference or a formula. The values in <list> may be literal values or cell references.
COS(<exp>)
Returns the cosine ff the (radian) angle <exp>.
COUNT(<list>)
Returns the number of non-blank cells In <list>.
Ranges may be included in the list. If the literal value 0 appears in <list>, this is evaluated as non-blank and therefore counted.
DATE(yy,mm,dd)
Returns the number of days elapsed between 30th Dec 1899 and the specified date (1.1.1900 = day 2).
In Lotus 1-2-3, 1900 is incorrectly taken to be a leap year, so values returned by this function will differ from those Of Lotus 1-2-3 by 1 until 1.3.1900. Future limit is 31.12.2078.
DAY(<exp>)
Given a number (<exp>) of elapsed days since 30.12.1899, returns the day of the month in which that day lies.
For example, the formula =DAY(31941) returns 13 because 31941 days after 30.12.1899 is 13th June 1987. Future limit is 31.12.2078.
Returns an illegal value interpreted as ERRor.
For example, using the IF function, the formula =IF(G12<3,ERR,B2) returns ERR if the contents of G 12 are less than 3 and returns the contents of B2 otherwise. This can then be tested with the ISERR function.
EXP(<exp>)
Returns the value of the arithmetic constant e (2.71828 ... ) raised to the power of the expression inside the brackets.
Returns the value 0.0 (the value returned by comparisons, e.g. =3<2 returns 0.0).
For example, B2 might contain a non-zero number to denote a certain event, so the formula =IF(B2=FALSE,D2,G2) would return the contents of cell D2 if cell B2 contains 0 or the contents of G2 otherwise.
FV(<payment>,<interest>,<term>)
Returns the future value of an annuity given the <interest> rate, the <payment> amount per period and the number of periods (<term>) according to the formula:
FV=<payment>*((1+<interest>)**<term>)- 1 /<interest>)
The interest rate is the period interest rate and is expressed in decimal form, i.e. 14% is expressed as .14.
HLOOKUP(<exp>,<range>,<offset>)
Performs a horizontal lookup on the values in the range of cells <range>.
The comparison values in the first row of the range must be in increasing order with no duplicates. The function finds the last cell in this row whose contents is not greater than the given index <exp> (unless this is the first cell in the range, when ERR Is returned). The function then returns the contents of the cell which lies <offset> rows below it. Non-integer values of <exp> are truncated to their integer part.
For example, in this worksheet:
| |B |C |D |E |F |2 | 1| 2| 3| 5| |3 | 14| 15| 16| 17| |4 | 18| 19| 20| 21| |5 | 22| 23| 24| 25| |6 | | | | |
| Formula |
Result |
|
| =HLOOKUP(1,B2:E5,3) | 22 | |
| =HLOOKUP(1.4,B2:E5,3) | 22 | |
| =HLOOKUP(3,B2:E5,2) | 20 | |
| =HLOOKUP(4,B2:E5, 1) | 16 | |
| =HLOOKUP(5,B2:E5,2) | 21 |
If the value of <offset> is negative or greater than or equal to the number of rows in the range then ERR is returned.
IF(<exp>, <then>, <else>)
If the condition <exp> returns non-zero (TRUE), the value of <then> is returned; otherwise, the value of <else> is returned.
For example, the formula =IF(B2=7,D2,G2) would return the contents of cell D2 if cell B2 contains 7 or the contents of G2 otherwise.
INT(<exp>)
Returns the integer (i.e. the whole number part) of <exp>. Negative numbers are rounded towards zero, so the formula =INT(5.7) returns the value -5.
IRR(<guess>,<range>)
Returns the approximate internal rate of return from a series of discounted cash flows (i.e. the interest rate which would give a net present value of zero on those cash flows).
The required arguments are an initial <guess> at the result and a cell <range>. The <range> contains a series of positive (income) and negative (payment) figures. Blank cells in <range> are permissible. The cash flows are taken to occur at the start of the period.
For example, in the next worksheet, the formula =IRR(B3,C3:C8) would return .06402. The interest rate is returned as a decimal, i.e. 14% would be returned as . 14.
| |B |C |D |2 |Guess|Range| |3 | 0.5|-1500| |4 | | 360| |5 | | 360| |6 | | 360| |7 | | 360| |8 | | 360|
An iterative method is used to calculate the result, and if convergence to a valid result does not occur within 20 iterations, the result ERR is returned. The interest rate returned by IRR is the period interest rate, where that period is the fixed interval between the cash flows. If you require the interest rate for a different period, you can convert the value returned by the IRR function.
Converting one period interest rate to the equivalent interest rate for a different period is not simply a matter of multiplying by the time factor.
For example, a monthly interest rate of 2% is not equivalent to an annual rate of 24%. The correct equation is based on the statement that equivalent interest rates produce the same discount after the same time. A cashflow which occurs after two years must have the same discount as a cash flow which occurs after 24 months.
The formula to convert one period interest rate (i1) into another (i2) is:
i2 = (1+i1)**(t2/t1) -1
where t1 and t2 are the corresponding periods, in the same units.
For example, if i1 is the annual rate and i2 is the monthly rate, then t1 is 12 months and t2 is 1 month, and the formula is:
i2 = (1+i1)**(1/12) - 1
Conversely, If i1 is the monthly rate and i2 is the annual rate, the formula is:
i2 = (1+i1)**12 - 1
Using this equation, we can calculate that a 2% monthly rate Is equivalent to a 26.8% annual rate. (The results are displayed as a decimal, for example 0.02; 0.268.)
In the UK, the APR (Annual Percentage Rate) is a standard way of quoting interest rates so that consumers can compare interest rates offered by different companies. The IRR function may be used to derive the APR provided the result is converted, If necessary, to an annual rate.
ISERR(<exp>)
Returns TRUE (1.0) if <exp> returns ERR; otherwise returns FALSE (0.0).
For example, if cell B2 contains the formula =B2/0 (illegal divide by zero) the formula =ISERR(B2) returns TRUE (1.0).
ISNA(<exp>)
Returns TRUE (1.0) if <exp> returns NA; otherwise returns FALSE (0.0).
For example, if cell B2 contains the formula IF(B3>99,NA,B3), the formula =ISNA(B2) returns TRUE (1.0) if the contents of B3 are greater than 99.
LN(<exp>)
Returns the natural (base e) logarithm of <exp>.
LOG(<exp>)
Returns the base 10 logarithm of <exp>.
MAX(<list>)
Returns the largest value in <list>. <list> may be literal values, cell references or cell ranges.
Text cells evaluate to zero.
MIN(<list>)
Returns the smallest value in <list>.
The list may consist of literal values, cell references or cell ranges. Text cells evaluate to zero.
MOD(<exp1>,<exp2>)
Returns the remainder from <exp1> divided by <exp2> (modulo).
The arguments may be numbers or cell references.
MONTH(<exp>)
Given a number (<exp>) of elapsed days since 30.12.1899, returns the month of the year in which that day lies.
For example, the formula =MONTH(31941) returns 6 because 31941 days after 30.12.1899 is 13th June 1987. Future limit is 31.12.2078.
Returns NA (Not Available).
For example, the formula =IF(B4>99,NA,B4) returns NA if the contents of B4 are greater than 99 and returns the contents of B4 otherwise.
NPV(<interest>,<range>)
Returns the Net Present Value of a series of future discounted cash flows for a given <interest> rate per period. <range> contains the positive (income) and negative (payment) cash flows.
The first cash flow is taken to occur at the end of the first period, and blank cells in the <range> are permissible. Subsequent cash flows are taken to occur at the end of subsequent periods.
For example, in the next worksheet, an initial payment of 4700 is followed by five receipts of 1600 at an interest rate of 14%. The formula =NPV(B2,C3:C7) would return the net present value of 5492.93 (to two decimal places). If you then subtract the initial payment you have the profit of 792.93 on the investment.
| |B |C |D |2 | 0.14|-4700| |3 | | 1600| |4 | | 1600| |5 | | 1600| |6 | | 1600| |7 | | 1600| |8 | | |
The interest rate should be given as a decimal, i.e. 14% should be given as . 14.
OPL(<cell>,<range>)
It is recommended that you use this function only when you have a sound working knowledge of OPL (Organiser Programming Language) and the way in which values are passed back from OPL procedures. Refer to your main Organiser manual for details of this subject.
The OPL function adds two facilities to the Spreadsheet:
- Any cell in the grid can call OPL procedures.
- An OPL procedure called by a cell in the grid can 'grab' the contents of other cells in the same worksheet.
For further details see chapter The OPL Function.
Returns the value of the mathematical constant Pi.
PMT(<principal>,<interest>,<term>)
Returns the mortgage payment per period given the amount of the loan (<principal>), the <interest> rate per period and the number periods (<term>).
The interest rate should be given as a decimal, i.e. 14% should be given as .14.
PV(<payment>,<interest>,<term>)
Returns the present value of an annuity, given the <payment> per period, the <interest> rate per period and the number of periods (<term>). For example, in this worksheet:
| |B |C |D |2 |Paymt| .95| |3 |Int | .1| |4 |Term | 12| |5 | | |
the formula =PV(C2,C3,C4) returns the value 647.30.
The interest rate should be given as a decimal, i.e. 14% should be given as .14.
Returns a random floating point number in the range 0.0 (inclusive) to 1.0 (exclusive).
ROUND(<exp1>,<exp2>)
Returns the value of a cell-content <exp1> rounded to <exp2> decimal places.
The value of <exp2> must be in the range -11 to +11. If the value of <exp2> is less than 0 the function returns the value of <exp2> rounded to the nearest 10**ABS(<exp2>).
For example:
| Formula |
Result |
|
| =ROUND(26858.30458,-3) | 27000 | |
| =ROUND(26858.30458,-1) | 26860 | |
| =ROUND(26858.30458,0) | 26858 | |
| =ROUND(26858.30458,1) | 26858.3 | |
| =ROUND(26858.30458,2) | 26858.3 | |
| =ROUND(26858.30458,5) | 26858.30458 |
Note that the zero in the second decimal place when the second parameter to ROUND is 2 isn't stored, nor displayed unless Format is set to 2 decimal places.
SIN(<exp>)
Returns the sine of the (radian) angle <exp>.
SQRT(<exp>)
Returns the square root of <exp>.
STD(<list>)
Returns the standard deviation of the numbers In <list>.
If all cells in <list> are empty, ERR is returned. Blank cells in <list> are ignored. Text cells evaluate to zero.
SUM(<list>)
Returns the sum of the values or contents of cells in <list>.
Text cells evaluate to zero.
TAN(<exp>)
Returns the tangent of the (radian) angle <exp>.
Returns the number of days elapsed since 30.12.1899.
For example, if the Organiser's date is set to 26 August 1987, the formula =TODAY returns the value 32015 because on that date there are 32015 elapsed days since 30.12.1899. Future limit is 31.12.2078.
Returns the value 1.0 (the value returned by comparisons, e.g. =3>2 returns 1.0).
For example. cell B2 might contain 1 to denote a certain event, so the formula =IF(B2=TRUE,D2,G2) would return the contents of cell D2 if cell B2 contains 1 or the contents of G2 otherwise.
VAR(<list>)
Returns the variance of the items in <list>.
The items in <list> may be literal values, cells or cell ranges. If there are no non-blank cells or values In <list>, ERR is returned. Text cells evaluate to zero.
VLOOKUP(<exp>,<range>,<offset>)
Performs a vertical lookup m the values In the range of cells <range>.
The comparison values in the first column of the range must be in Increasing order with no duplicates. The function finds the last cell in this column whose contents is not greater than the given index <exp> (unless this is the first cell in the range, when ERR is returned). The function then returns the contents of the cell which lies <offset> columns to the right. Non-integer values of <exp> are truncated to their integer part.
For example, in this worksheet:
| |B |C |D |E |F |2 | 1| 2| 3| 5| |3 | 14| 15| 16| 17| |4 | 18| 19| 20| 21| |5 | 22| 23| 24| 25| |6 | | | | |
these are the values returned:
| Formula |
Result |
|
| =VLOOKUP(1,B2:E5,3) | 22 | |
| =VLOOKUP(1.4,B2:E5,3) | 22 | |
| =VLOOKUP(3,B2:E5,2) | 20 | |
| =VLOOKUP(4,B2:E5, 1) | 16 | |
| =VLOOKUP(5,B2:E5,2) | 21 |
If the value of <offset> is n egative or greater than or equal to the number of columns in the range then ERR is returned.
YEAR(<exp>)
Given a number (<exp>) of elapsed days since 30.12.1899, returns the year since 1900 in which that day lies.
For example, the formula =MONTH(31941) returns 87 because 31941 days after 30.12.1899 is 13th June 1987. Future limit is 31.12.2078.
The OPL Function
It is recommended that you use this function only when you have a sound working knowledge of OPL (Organiser Programming Language) and the way in which values are passed back from OPL procedures. Refer to your Organiser manual for further details.
NB. Formulae containing the OPL function cannot be Exported. Each cell referring to the function will display =ERR on the other computer.
The OPL function adds three facilities to the Spreadsheet:
- Any cell in the grid can call OPL procedures
- An OPL procedure called by a cell can 'grab' the contents of other cells In the same worksheet.
- An OPL procedure can return a value to a cell.
Calling Procedures
The OPL function is entered into a cell as a formula. Then when the grid is recalculated, in order to work out this formula the gild calls a named procedure, which then returns a value to the cell in which the formula was entered.
The OPL function has this syntax:
OPL(<cell>,<range>)
<cell> is the reference of a cell containing an OPL procedure name.
The procedure name must be a valid one, excluding the trailing colon. The procedure itself:
- Must be stored in either the internal memory of the Organiser, or a Datapak or Rampak fitted to the machine.
- Must not be a string procedure (the OPL function will return ERR).
- Must not have any declared parameters (values are passed to the procedure from the Spreadsheet by means of the two functions explained below).
<range> is a cell range whose contents are used as the input values of the procedure named in <cell>. The cells:
- May be blank
- May contain numbers, formulae or text.
Even if <range> contains only one cell, <range> must still be a fully specified range, in the format B2:B2.
When the current worksheet is recalculated, the procedure named in <cell> takes as its input value the value contained in the first cell in <range>. The procedure runs as normal, then returns a value to <cell>. Then, if there is another cell in <range>, the value In this cell Is used as the input value, and the new result returned to <cell>. This continues until the end of <range>.
New Functions
Two new functions are added to OPL while the Spreadsheet is installed in the Organiser: CELL: and CELL$:.
These functions pass to the procedure named in <cell> the value contained in the first cell in <range>, then in the second and so on until the end of the range. They ignore blank cells.
- CELL: returns a floating point value from the 'next' cell.
- CELL$: returns a string value from the 'next' cell
Parameter Order
The values in the cells in <range> are accessed by the named procedure from left to right and from top to bottom, i.e. in the order:
1 2
3 4
Once the contents of one cell have been 'grabbed’ from the Spreadsheet, an internal pointer is set to the next non-blank cell in the range.
Possible Errors
- Using CELL$: when the next cell contains a number, or CELL: when the next cell contains text:
Use the appropriate function. - Attempting to access cells in <range> more times than there are non-blank cells.
Access either the exact number of cells or a number less than the number of cells.
Unless trapped with OPL's ONERR command, these errors are reported in the usual way, the procedure ends and the OPL function in the Spreadsheet returns the value ERR.
When the OPL function is used in a Spreadsheet, the procedure name(s) present in the grid call their procedures every time the worksheet Is recalculated. You should therefore set the recalculation mode to Manual with the Recalc command before setting up the worksheet.
Example: Share Portfolio
The share portfolio worksheet set up in the tutorial can be improved by using the OPL function to:
- Prompt for each of the new daily share prices
- Report the day's total value of the portfolio directly to the screen (once the Spreadsheet has finished calculating).
This means that you can find out the result you designed the Spreadsheet to calculate, but without having to actually see and move around the grid itself.
A first procedure, called ASK:, prompts for a price for each of the shares held and inserts that price into the appropriate cell in the worksheet. Then a second procedure, called TELL:, 'grabs' the grand total from the cell in which it has been worked out and prints it to the screen.
Here is the original worksheet:
| |QTY |TODAY|SUB-T |TOTAL |F |PORT| | | | | |BT | 1000| 2.37| 2370.00| 3190.00| |TSB | 500| 0.9| 450.00| | |GAS | 200| 0.75| 150.00| | |BA | 200| 1.1| 220.00| |
Either load this worksheet if you had originally saved it, or enter it afresh if you hadn't (see tutorial example for details). Then:
- Press ON/CLEAR to leave the grid without losing the worksheet, and select Prog from the Organise main menu.
- Write these two procedures:
ASK:
LOCAL a
PRINT "Todays value of"
PRINT CELL$:;":";
INPUT a
RETURN a
TELL:
PRINT "Todays total"
PRINT "=",CELL:
GET
- Translate them to cheek you've typed them in correctly, then save them under the names ASK: and TELL: respectively.
- Return to the worksheet.
- Set the recalculation mode to Manual. This is important because it stops the worksheet from recalculating until all the day's share prices have been entered, not after each one.
The ASK: procedure will be called from each cell in turn where the price of a share was entered in the original worksheet. The number you then enter (INPUT a) is entered into the cell which called the procedure. This needs to be a different cell for each share price, so:
- Enter into cell F2 the text ASK
- Enter into cell C3 the formula =OPL($F$2,A3:A3)
When you press EXE the formula is evaluated. Enter today's price of the BT shares, as asked:
Todays value of BT:
- Now use the Copy command to copy this formula into cells C4 to C6, the other price cells. When you press EXE to enter the 'Copy to' range, the share cells don't prompt for today's value, since the grid won't recalulate until you press EXE again.
The OPL function has as its parameters:
- The absolute cell reference $F$2 (the cell which contains the name of the procedure to be called ASK:)
- A single-cell range reference to the row title cell, i.e. that cell at the left of the current row which contains the share name.
- Press EXE to enter each of today's prices in turn. You are returned to the grid, with today's total displayed in cell E3.
To make the grid automatically tell you today's total:
- Enter into cell F3 the text TELL
- Enter Into cell E5 the formula: =OPL (F3, E3:E3)
This function performs the procedure named in cell F3 (TELL:) on the contents of the single-cell range E3:E3 i.e. the cell displaying the folio total. When you press EXE to enter the formula, the screen tells you the total value of your shares, like this:
Todays total = 3190
- Press any key to return to viewing the grid.
- Press EXE again and you will be asked again for the share prices and told today's total.
- Press ON/CLEAR to leave the grid, or press MODE and Save it.
To improve this worksheet, make sure that the folio total returned by TELL: is a rounded figure. This is necessary because, though cell E3 displays the result to only two decimal places, it stores it to more than two - and it is the stored number which the TELL: procedure takes and displays on the screen. It would be Inappropriate to show a result of more than 2 decimal places.
- Enter into cell E4 the formulae: =ROUND(E3,2).
This takes the total calculated in cell E3 and rounds it to two decimal places.
- Change the formula in cell E5 to: =OPL (F3, E4:E4)
so that TELL: takes the rounded value in cell E4, not the full value in E3.
- Use Format to make cell E4 show two decimal places (Otherwise any zero in the second decimal place will not be displayed.)