See also: How do I search for a function?



PDL::Doc::Perldl - commands for accessing PDL doc database from 'perldl' shell


This module provides a simple set of functions to access the PDL documentation of database, for use from the perldl or pdl2 shells as well as the pdldoc command-line program.

Autoload files are also matched, via a search of the PDLLIB autoloader tree. That behavior can be switched off with the variable $PERLDL::STRICT_DOCS (true: don't search autoload tree; false: search the autoload tree.)

Currently, multiple matches are not handled very well.


 use PDL::Doc::Perldl; # Load all documenation functions


The description contains the misleading word "simple".



Regex search PDL documentation database

 apropos 'text'
 pdl> apropos 'pic'
 rpic            Read images in many formats with automatic format detection.
 rpiccan         Test which image formats can be read/written
 wmpeg           Write an image sequence ((x,y,n) piddle) as an MPEG animation.
 wpic            Write images in many formats with automatic format selection.
 wpiccan         Test which image formats can be read/written

To find all the manuals that come with PDL, try

  apropos 'manual:'

and to get quick info about PDL modules say

  apropos 'module:'

You get more detailed info about a PDL function/module/manual with the help function


Internal routine to search docs database and autoload files


Internal interface to the PDL documentation searcher


Internal helper routine that finds and returns documentation in the autoloader path, if it exists. You feed in a topic and it searches for the file "${topic}.pdl". If that exists, then the filename gets returned in a match structure appropriate for the rest of finddoc.


Prints usage information for a PDL function

 Usage: usage 'func'
   pdl> usage 'inner'
   inner           inner prodcuct over one dimension
                   (Module PDL::Primitive)
   Signature: inner(a(n); b(n); [o]c(); )


prints signature of PDL function

 sig 'func'

The signature is the normal dimensionality of the function's arguments. Calling with different dimensions doesn't break -- it causes threading. See PDL::PP for details.

  pdl> sig 'outer'
    Signature: outer(a(n); b(m); [o]c(n,m); )


Describe a perl and/or PDL variable or expression. Useful for determining the type of an expression, identifying the keys in a hash or a data structure, or examining WTF an unknown object is.

 Usage: whatis $var
        whatis <expression>


print documentation about a PDL function or module or show a PDL manual

In the case of multiple matches, the first command found is printed out, and the remaining commands listed, along with the names of their modules.

 Usage: help 'func'
 pdl> help 'PDL::Tutorials' # show the guide to PDL tutorials
 pdl> help 'PDL::Slices'    # show the docs in the PDL::Slices module
 pdl> help 'slice'          # show docs on the 'slice' function


provides information on the bad-value support of a function

And has a horrible name.

 badinfo 'func'