| CC: | tim.culmer [...] itdev.co.uk |
| Subject: | Warnings occur when running under -w flag |
The following code generates "uninitialized value" warnings:
#!/usr/local/bin/perl -w
use LineGraphDataset;
my $dataset = LineGraphDataset -> new(-name => 'Dataset 1', -yArray =>
[0..20]);
The warnings are caused by testing the object variables to see if they
are defined.
Instead of writing: if($variable == undef)
This could be used: unless(defined($variable))
This problem is only picked up when running the class under the -w flag.
There is also an additional problem in the documentation (and in the
documentation of Tk::LineGraph) where -xData and -yData options are used
in an example, but the names of these options are actually -xArray and
-yArray in the code.
I have fixed both these issues in the attached version the
Tk::LineGraphDataset module.
Thanks,
Tim
| Subject: | LineGraphDataset.pm |
$Tk::LineGraphDataset::VERSION = '0.01';
package LineGraphDataset;
# This is a LineGraphDataset object.
# It can be graphed by LineGraph
$DataSetCount = 0;
sub new {
# create a new LineGraphDataset object
my($class, %args) = @_;
bless(\%args, $class);
my $self = \%args;
$self->{-index} = $DataSetCount++;
$self->{-active} = 1; # yes, active
$self->{-color} = "none" unless(defined($self->{-color}));
$self->{-y1} = 0 unless(defined($self->{-y1}));
$self->{-yAxis} = "Y" unless(defined($self->{-yAxis}));
die "Each LineGraphDataset requires a name.\n" unless(defined($self->{-name}));
die "Each LineGraphDataset requires a Y array of data points.\n" unless(defined($self->{-yArray}));
my @ya;
unless(defined($self->{-yArray})) {
foreach my $e (@{$self->{-yArray}}) {
push @ya, $e;
}
$self->{-yArray} = \@ya; # now the dataset owns the data
}
my @xa;
unless(defined($self->{-xArray})) {
foreach my $e (@{$self->{-xArray}}) {
push @xa, $e;
}
$self->{-yArray} = \@xa; # now the dataset owns the data
}
return($self);
}
sub get {
# get any attribute
my($self,$attr) = @_;
return($self->{$attr});
}
sub set {
# set/defind an attribute
# -att => value is the format
# print "args for set @_ \n";
my($self, %att) = @_;
foreach my $k (keys(%att) ) {
$self->{$k} = $att{$k};
}
foreach my $k (keys(%$self) ) {
# print "LineGraphDataset hash <$k> <$self->{$k}> \n";
}
}
1;
=head1 NAME
LinePlotDataset - An Object into which to store data to be plotted by the LineGraph widget.
=head1 DESCRIPTION
LinePlotDataset is an object into which data and meta data can be stored.
This object can be plotted by the LineGraph widget.
=head1 CONSTRUCTOR
new(-yArray => Y data array
-name => dataset name,
-yAxis => "Y|Y1",
-color => line Color,
-xArray => X data array);
The Y array data and the dataset name are required. Other parameters are optional.
The yAxis defaults to the Y (left hand) axis. The color for the graph of the dataset defaults
to one the plot default colors. The X array data defaults to the integers (0 .. size of yArray).
The Dataset objects copies the data arrays.
=head1 EXAMPLE
use Tk;
use Tk::LineGraph;
use Tk::LineGraphDataset;
my $mw = MainWindow->new;
my $cp = $mw->LineGraph(-width=>500, -height=>500, -background => snow)->grid;
my @yArray = (1..5,11..18,22..23,99..300,333..555,0,0,0,0,600,600,600,600,599,599,599);
my $ds = LineGraphDataset->new(-yArray=>\@yArray,-name=>"setOne");
$cp->linePlot(-dataset=>$ds);
MainLoop;
=head1 METHODS
=item B<get(option);>
Returns the current value of the option. Options are listed in the constructor.
=item B<set(option , value);>
Sets the option to value. Options are listed in the constructor.
=head1 AUTHOR
Tom Clifford (Still_Aimless@yahoo.com)
Copyright (C) Tom Clifford. All rights reserved.
This program is free software; you can redistribute it and/or
modify it under the same terms as Perl itself.
=head1 KEYWORDS
Graph 2D Axis Graph Dataset
=cut