navigation map

  1: Introduction
  2: Simple example
  3: Invocation
  4: Finer Control
  5: X-Y Plots
  6: Contour Plots
  7: Image Plots
  8: Examples
  9: Gri Commands
  10: Programming
  11: Environment
  12: Emacs Mode
  13: History
  14: Installation
  15: Gri Bugs
  16: Test Suite
  17: Gri in Press
  18: Acknowledgments
  19: License

index.html#Top Programming.html#Programming Gri: defaults Gri: long command lines index.html#Top Gri: long command lines

10.2: Online Help

Type `help' to get a list of available commands and other topics of interest. Here's how Gri responds

Type `help' followed by a command-name:
 assert      cd            close         convert
 create      debug         delete        differentiate
 draw        expecting     filter        flip
 get         help          if            ignore
 input       insert        interpolate   list
 ls          mask          move          new
 open        pwd           query         quit
 read        regress       reorder       rescale
 resize      return        rewind        set
 show        skip          sleep         smooth
 source      sprintf       state         superuser
 system      write
Or type `help -' followed by a topic from this list:
 example     extending     files         math
 strings     synonyms      variables     manual

Some commands have more words than shown. You can type these additional words to narrow the help down; otherwise Gri will give you help on all commands that begin with the indicated words. For example, try `help set' and `help set x'. When you ask for help on a multi-word command, Gri tells you about all commands which begin with the words you've typed. Thus,

help draw
help draw zero
help draw zero line

narrow in on the command `draw zero line'. The response to the most complete request is

`draw zero line [horizontally|vertically]'
  draw zero line
    Draw line y=0 if it is within axes
  draw zero line horizontally
    Draw line y=0 if it is within axes
  draw zero line vertically
    Draw line x=0 if it is within axes

The part enclosed in angled quotes is the syntactical description of the command. (NOTE: The square brackets indicate an optional word (in this case) or words. The vertical bar indicates that either the item on the left or the item on the right may appear; it is a logical OR operator. The only other special characters in syntax descriptions are the braces `{}', which are used to enclose multiple words which act as one unit; they are used to clarify the choices presented to the OR operator.) Following the syntactical description are examples. Each example is indented 2 spaces, and a description of it (which always starts with an upper-case character and ends with a period, to indicate that it is an English description) follows that, indented by an additional 2 spaces.

navigation map