index.txt
VISI(1) General Commands Manual VISI(1) NAME visi - mathematical spreadsheet SYNOPSIS visi [ file ] DESCRIPTION Visi is a tabular mathematical worksheet for data analysis. If a file is specified, commands are read from that file when visi first starts. Visi works only on cursor-controlled terminals such as the HP2621, and requires the environment variable TERM (see environ(7)) to be set ap‐ propriately. Visi prompts for input at the top of the screen with `>>'. Input has one of the forms, command parameters variable = expression variable = "string" where a variable is a letter and number sequence, for example: `A2, B10, BB23.' These variables represent locations on the worksheet; A2 is column A, row 2. If you type, in any order, A1 = A2 + 5 A2 = 10 the values 15 and 10 will appear on the screen. If you later type A2 = 20 the values will be updated to 25 and 20. Visi treats upper and lower case letters as identical. Expressions are parsed, and standard mathematical precedence is re‐ tained. The operators +, -, *, /, ** (or ^) can be used in expres‐ sions. Commands copy [ file ] Copy the screen image to the file. If a file is not speci‐ fied, visi will prompt for one. debug Toggle a flag to give yacc(1) debugging output, very unread‐ able. duplicate p1 thru p2 at p3 Duplicate a block of definitions in another portion of the screen. P1 and p2 are the upper left corner and the lower right corner of the block to be duplicated. P3 is the upper left corner of the destination. edit Edit the commands list. If the environment variable `ED' is set, it is used as the name of the editor. Otherwise, ed(1). is called. help Display a brief synopsis of the commands. list List the current definitions on the terminal. quit Quit the program. read [ file ] Read input lines from the file. If a file is not specified, visi will prompt for one. redraw Redraw the screen in the event the terminal output was cor‐ rupted. replicate p1 at p2 thru p3 Replicate the single definition at p1 throughout the block from p2 in the upper left corner thru p3 in the lower right. scale [ column ] nnn Change the scale of the specified column, or of the entire tableau if a column is not specified. The scale nnn is the number of decimal places that are displayed to the right of the decimal point. Calculations are done in double precision regardless of scale. shift direction [ nnn ] Shift the current screen in any direction. The screen is only a window on the tableau. To see other portions of the tableau, the screen must be shifted. Valid directions are: up, down, left, right. Nnn is the number of positions to shift the screen (default 1). shell Invoke /bin/sh as an inferior process to visi. ver Print the current version number of visi. width column nnn Change the width of a column on the display, or of the entire tableau if no column is specified. write [ file ] Write commands to a file. If a file is not specified, visi will prompt for one. Built-in Functions abs(e) Absolute value of e. acos(e) Arc cosine of e. asin(e) Arc sine of e. atan(e) Arc tangent of e. atan2(e1,e2) Arc tangent of e1/e2. cos(e) Cosine of e. exp(e) Exponential function of e. gamma(e) Log of the gamma function of e. hypot(e1,e2) Square root of the sum of the squares of e1 and e2. int(e) The integer part of e (truncated toward zero.) log(e) Natural log of e. pi The constant 3.14159265358979.... pow(e1,e2) Same as e1^e2. sin(e) Sine of e. sqrt(e) Square root of e. Other Special Definitions position[e1,e2] The quantity at row e1, column e2 of the tableau. Numbering for the columns is A = 1, B = 2, ..., AA = 27, and so on. ROW The row number of this entry. COL The column number of this entry. SEE ALSO ed(1), exp(3), sin(3) FILES /usr/lib/visi.help BUGS A circular list of variable declarations can cause visi to hang in a loop. Scale does truncation, not rounding. VISI(1)