--- DSCALC Onscreen Help --- by Dick Sowa A spreadsheet is simply a grid of rows and columns. At the intersection of each row and column is a CELL. Row numbers are displayed along the left side of the screen, (ex:R01,R02...). Column numbers are along the top edge, (ex: C01, C02....). Each cell is either blank or contains data of some sort. Blank cells are ignored during calculations and are not saved to disk. Data stored in one cell can be used to calculate values for another cell. Results of one calculation can be used to calculate values for other cells. I call this formula 'nesting'. === USING DSCALC === CELL REFERENCES:Cells are referenced by row and column, using the form äR01C13å. When the reference is to another formula, the calculated value of the other formula is used. These references are used within mathematical expressions just like any variable. For example: 3*äR13C06å/3.14 Using cell references is one way to copy data from one cell to another. The SUM command specifies a range of cells to be added together. For example: SUMäR08C14-25å or SUMäR01-25C09å In the first example we are adding all the values (or calculated values) in row 8 between, and including, columns 14 through 25. Similarly, in the second example rows 1 through 25 in column 9. Column and row numbers can be in any order, (rows before columns or columns listed before rows). 1. Cell references cannot be made to blank or text cells. 2. Use no spaces within the brackets. 3. Make sure each cell reference is to value cells or to cells which can be calculated first. 4. !!!!!!!! in the cell after a calc- ulation means the value calculated is too lengthy, (has too many digits), to fit in the cell. Try using the INT() function to drop any decimals. 5. The SUM command CANNOT be included with any other formulas. The form above must be the only formula entry in a cell. CURSOR KEYS:Cursor keys are used only to move the cursor from one cell to another. CELL CONTENTS: If any, cell contents are displayed below the function key menu and in the cell itself, (up to 8 characterrs). NOTE:Formulas are displayed below the function key menu. The CALCULATED VALUE of the formula is displayed in the cell. FUNCTION KEYS are active whenever the function key menu is displayed at the screen bottom. F1 Values: Floating point number. 8 characters max including demimal. F2 Formulas: Standard BASIC syntax. 79 characters maximum. Cell references are permitted. 100 formulas max per spreadsheet. F5 Text: 8 characters maximum. F7 Help: Displays this file on your screen. Make sure your system disk is in drive 8 first. F2 Load: Will load a previously saved spreadsheet from disk. You will be prompted for a filename. CAUTION: Current sheet will be overwritten by the loaded file. Loaded files are no calculated. F4 Save: Saves currently displayed sheet to disk file. You are prompted for a filename. Will not overwrite a file with the same name. F6 Print: Allows printing to your printer. F8 RECALC: Takes entered data and formulas, calculates the results and displays them on the screen. ==== ERROR MESSAGES ==== DOS msgs: Standard disk error msgs. BLANK OR TEXT CELL REFERENCE: One or more of your cell references calls a blank cell or text cell. NO REFERENCE TO VALUE CELL: This message means that all cell references are to other formulas, and none to a value cell. INFINITE LOOP: One formula calls another formula cell, which in turn calls another, which eventually refers back to the original formula cell. Cell references have to end somewhere. Think of cell references as branches in a tree, spreading out but never closing back on itself. NESTING EXCEEDS 20 LEVELS: One formula cell calls another, which in turn calls another, etc. This heirarchy or branching is limited to 20 levels maximum. This is an arbitrary limit I set to simplify the programming. It should be plenty. SYNTAX ERROR IN CELL: The syntax of a formula or SUM command is not correct. The offending cell is identified for you.