NAME

PDL::Graphics::Prima::Limits - defining a couple of useful constants

DESCRIPTION

You probably won't ever need to use this module explicitly, but you will likely use the constants defined here to manipulate axis autoscaling. This module defines the constants lm::Auto and lm::Hold. If the explanation below does not make sense, these constants are also discussed in PDL::Graphics::Prima::Axis, PDL::Graphics::Prima::Simple, and elsewhere.

lm::Auto

When you set an axis's min or max to lm::Auto, you turn on min or max autoscaling:

# Set the x-min to -5 for now...
$plot->x->min(-5);

# Turn on autoscaling for x-min:
$plot->x->min(lm::Auto);

lm::Hold

This constant gives a shorthand for changing from autoscaling to non-autoscaling. For example, suppose you are building a plot from multiple data sets and want to autoscale based on the first few but not for the remaining. In that case you might say:

$plot->dataSets->{'data'} = ds::Pair($x, $y);
$plot->y->minmax(lm::Hold, lm::Hold);
$plot->dataSets->{'model'} = ds::Func(\&my_func);

You can achieve the same ends like so:

$plot->dataSets->{'data'} = ds::Pair($x, $y);
$plot->y->minmax($plot->y->minmax);
$plot->dataSets->{'model'} = ds::Func(\&my_func);

If you just wanted to set the min to hold, you could use lm::Hold like this:

$plot->y->min(lm::Hold);

which is equivalent to:

$plot->y->min($plot->y->min);

Also note that the return value of $plot->y->min returns different things depending on whether you are using scalar or list context. (Yes, that's an Axis thing, not a Limits thing, but it bears repeating here anyway.)

AUTHOR

David Mertens (dcmertens.perl@gmail.com)

SEE ALSO

This is a component of PDL::Graphics::Prima. This library is composed of many modules, including:

PDL::Graphics::Prima

Defines the Plot widget for use in Prima applications

PDL::Graphics::Prima::Axis

Specifies the behavior of axes (but not the scaling)

PDL::Graphics::Prima::DataSet

Specifies the behavior of DataSets

PDL::Graphics::Prima::Internals

A dumping ground for my partial documentation of some of the more complicated stuff. It's not organized, so you probably shouldn't read it.

PDL::Graphics::Prima::Limits

Defines the lm:: namespace

PDL::Graphics::Prima::Palette

Specifies a collection of different color palettes

PDL::Graphics::Prima::PlotType

Defines the different ways to visualize your data

PDL::Graphics::Prima::Scaling

Specifies different kinds of scaling, including linear and logarithmic

PDL::Graphics::Prima::Simple

Defines a number of useful functions for generating simple and not-so-simple plots

LICENSE AND COPYRIGHT

Portions of this module's code are copyright (c) 2011 The Board of Trustees at the University of Illinois.

This module's documentation are copyright (c) 2011-2012 David Mertens.

All rights reserved.

This module is free software; you can redistribute it and/or modify it under the same terms as Perl itself.