<html> <head> <title>Siag - Concepts</title> </head> <body> <h1>Concepts</h1> <dl> <dt><b>label</b> <dd>A descriptive text in a cell that is not used for any calculations. <dt><b>expression</b> <dd>A string in a cell which evaluates to a (floating point) numeric result. The simplest expression is a number; more complicated expressions can be entered in Scheme syntax. <p> The Scheme used in Siag has a few extensions to make it more useful in a spreadsheet. These new functions have been added: <ul> <li><b>(row)</b> Returns the row number of the cell which is being computed. <li><b>(col)</b> Returns the column number of the cell which is being computed. <li><b>(get-cell </b><i>row col</i><b>)</b> Returns the contents of the cell with the given coordinates. <li><b>(sum </b><i>start end</i><b>)</b> Returns the sum of all the cells in the rectangle between <i>start</i> and <i>end</i>. </ul> <dt><b>grid</b> <dd>The area where labels and expressions are displayed. <dt><b>colnum</b> <dd>The grey area where column numbers are displayed. <dt><b>rownum</b> <dd>The grey area where row numbers are displayed. <dt><b>mark</b> <dd>The "other" standard position in the document, which is used for commands which need two coordinates. <dt><b>point</b> or <b>current cell</b> <dd>The cell where labels and expressions are entered. The current cell can be moved using arrow keys, the mouse and other methods. <dt><b>block</b> <dd>The block is a rectangular area which is displayed in inverse. It is used for commands which operate on a whole range of cells. </dl> <hr> <address>Ulric Eriksson - January 1997 - ulric@siag.nu</address> </body> </html>
