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NAME

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

DESCRIPTION

This module provides a set of functions to access the PDL documentation database, for use from the perldl shell 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.)

In the interest of brevity, functions that print module names (at the moment just "apropos" and "usage") use some shorthand notation for module names. Currently-implemented shorthands are

  • P:: (short for PDL::)

  • P::G:: (short for PDL::Graphics::)

To turn this feature off, set the variable $PERLDL::long_mod_names to a true value. The feature is assumed to be on for the purposes of this documentation.

SYNOPSIS

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

FUNCTIONS

apropos

Regex search PDL documentation database

apropos 'text'
pdl> apropos 'pic'
PDL::IO::Pic P::IO::Pic Module: image I/O for PDL
grabpic3d P::G::TriD Grab a 3D image from the screen.
rim P::IO::Pic Read images in most formats, with improved RGB handling.
rpic P::IO::Pic Read images in many formats with automatic format detection.
rpiccan P::IO::Pic Test which image formats can be read/written
wim P::IO::Pic Write a pdl to an image file with selected type (or using filename extensions)
wmpeg P::IO::Pic Write an image sequence (a (3,x,y,n) byte pdl) as an animation.
wpic P::IO::Pic Write images in many formats with automatic format selection.
wpiccan P::IO::Pic 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

PDL::Doc::Perldl::search_docs

Internal routine to search docs database and autoload files

PDL::Doc::Perldl::finddoc

Internal interface to the PDL documentation searcher

find_autodoc

Internal routine that finds and returns documentation in the PDL::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.

usage

Prints usage information for a PDL function

Usage: usage 'func'
pdl> usage 'inner'
inner P::Primitive Inner product over one dimension
Signature: inner(a(n); b(n); [o]c())

sig

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 broadcasting. See PDL::PP and PDL::Broadcasting for details.

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

whatis

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>

help

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

badinfo

provides information on the bad-value support of a function

And has a horrible name.

badinfo 'func'
pdl> badinfo 'inner'
Bad value support for inner (in module PDL::Primitive)
If "a() * b()" contains only bad data, "c()" is set bad. Otherwise "c()"
will have its bad flag cleared, as it will not contain any bad values.