Chapters:
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
Indices:
Concepts
Commands
Variables

### 9.3.6: ``debug`'

    `debug [.n.]|[clipped values in draw commands]|off'

With no optional parameters, sets the value of ``..debug..`' to 1. (Normally, ``..debug..`' is 0.) You may use ``..debug..`' in ``if`' statements, etc. Note that ``..debug..`' is also set to 1 when gri is invoked with the commandline switch ``-d`'.

With ``.n.`' specified, ``..debug..`' is set to ``.n.`'; a value of zero for ``.n.`' turns debugging off, while 1 turns it on. Higher values may be used for deeper debugging, if you choose:

    if {rpn ..debug.. 2 <}
      # Code to do if ..debug.. is greater than 2.
    end if

Note that you can assign to ``..debug..`' as you can to any other variable; ``debug .n.`' is equivalent to ``..debug.. = .n.`'. With the ``clipped`' option, Gri prints any clipped data encountered during any ``draw ...`' commands, EXCEPT in the case of ``postscript`' clipping, where no check is possible. (Note that ``..debug..`' is not affected.)

All these forms of debugging are cancelled by ``debug off`'.