ChartDirector Ver 5.0 (Perl Edition)

Parametric Curve Fitting




This example demonstrates parametric curve fitting.

In addition to linear regression, ChartDirector also supports polynomial, exponential and logarithmic regression. To create these curves, a TrendLayer object is created using XYChart.addTrendLayer, and the regressive type is set using TrendLayer.setRegressionType.

Source Code Listing

[Standalone Version] perldemo\paramcurve.pl
#!/usr/bin/perl
use perlchartdir;

# The XY data of the first data series
my $dataX0 = [10, 35, 17, 4, 22, 29, 45, 52, 63, 39];
my $dataY0 = [2.0, 3.2, 2.7, 1.2, 2.8, 2.9, 3.1, 3.0, 2.3, 3.3];

# The XY data of the second data series
my $dataX1 = [30, 35, 17, 4, 22, 59, 43, 52, 63, 39];
my $dataY1 = [1.0, 1.3, 0.7, 0.6, 0.8, 3.0, 1.8, 2.3, 3.4, 1.5];

# The XY data of the third data series
my $dataX2 = [28, 35, 15, 10, 22, 60, 46, 64, 39];
my $dataY2 = [2.0, 2.2, 1.2, 0.4, 1.8, 2.7, 2.4, 2.8, 2.4];

# Create a XYChart object of size 540 x 480 pixels
my $c = new XYChart(540, 480);

# Set the plotarea at (70, 65) and of size 400 x 350 pixels, with white background
# and a light grey border (0xc0c0c0). Turn on both horizontal and vertical grid lines
# with light grey color (0xc0c0c0)
$c->setPlotArea(70, 65, 400, 350, 0xffffff, -1, 0xc0c0c0, 0xc0c0c0, -1);

# Add a legend box with the top center point anchored at (270, 30). Use horizontal
# layout. Use 10 pts Arial Bold Italic font. Set the background and border color to
# Transparent.
my $legendBox = $c->addLegend(270, 30, 0, "arialbi.ttf", 10);
$legendBox->setAlignment($perlchartdir::TopCenter);
$legendBox->setBackground($perlchartdir::Transparent, $perlchartdir::Transparent);

# Add a title to the chart using 18 point Times Bold Itatic font.
$c->addTitle("Parametric Curve Fitting", "timesbi.ttf", 18);

# Add titles to the axes using 12 pts Arial Bold Italic font
$c->yAxis()->setTitle("Axis Title Placeholder", "arialbi.ttf", 12);
$c->xAxis()->setTitle("Axis Title Placeholder", "arialbi.ttf", 12);

# Set the axes line width to 3 pixels
$c->yAxis()->setWidth(3);
$c->xAxis()->setWidth(3);

# Add a scatter layer using (dataX0, dataY0)
$c->addScatterLayer($dataX0, $dataY0, "Polynomial", $perlchartdir::GlassSphere2Shape,
    11, 0xff0000);

# Add a degree 2 polynomial trend line layer for (dataX0, dataY0)
my $trend0 = $c->addTrendLayer2($dataX0, $dataY0, 0xff0000);
$trend0->setLineWidth(3);
$trend0->setRegressionType(perlchartdir::PolynomialRegression(2));

# Add a scatter layer for (dataX1, dataY1)
$c->addScatterLayer($dataX1, $dataY1, "Exponential",
    $perlchartdir::GlassSphere2Shape, 11, 0x00aa00);

# Add an exponential trend line layer for (dataX1, dataY1)
my $trend1 = $c->addTrendLayer2($dataX1, $dataY1, 0x00aa00);
$trend1->setLineWidth(3);
$trend1->setRegressionType($perlchartdir::ExponentialRegression);

# Add a scatter layer using (dataX2, dataY2)
$c->addScatterLayer($dataX2, $dataY2, "Logarithmic",
    $perlchartdir::GlassSphere2Shape, 11, 0x0000ff);

# Add a logarithmic trend line layer for (dataX2, dataY2)
my $trend2 = $c->addTrendLayer2($dataX2, $dataY2, 0x0000ff);
$trend2->setLineWidth(3);
$trend2->setRegressionType($perlchartdir::LogarithmicRegression);

# Output the chart
$c->makeChart("paramcurve.png")

[CGI Version] perldemo_cgi\paramcurve.pl
#!/usr/bin/perl

# Include current script directory in the module path (needed on Microsoft IIS).
# This allows this script to work by copying ChartDirector to the same directory
# as the script (as an alternative to installation in Perl module directory)
use File::Basename;
use lib dirname($0) =~ /(.*)/;

use perlchartdir;

# The XY data of the first data series
my $dataX0 = [10, 35, 17, 4, 22, 29, 45, 52, 63, 39];
my $dataY0 = [2.0, 3.2, 2.7, 1.2, 2.8, 2.9, 3.1, 3.0, 2.3, 3.3];

# The XY data of the second data series
my $dataX1 = [30, 35, 17, 4, 22, 59, 43, 52, 63, 39];
my $dataY1 = [1.0, 1.3, 0.7, 0.6, 0.8, 3.0, 1.8, 2.3, 3.4, 1.5];

# The XY data of the third data series
my $dataX2 = [28, 35, 15, 10, 22, 60, 46, 64, 39];
my $dataY2 = [2.0, 2.2, 1.2, 0.4, 1.8, 2.7, 2.4, 2.8, 2.4];

# Create a XYChart object of size 540 x 480 pixels
my $c = new XYChart(540, 480);

# Set the plotarea at (70, 65) and of size 400 x 350 pixels, with white background
# and a light grey border (0xc0c0c0). Turn on both horizontal and vertical grid lines
# with light grey color (0xc0c0c0)
$c->setPlotArea(70, 65, 400, 350, 0xffffff, -1, 0xc0c0c0, 0xc0c0c0, -1);

# Add a legend box with the top center point anchored at (270, 30). Use horizontal
# layout. Use 10 pts Arial Bold Italic font. Set the background and border color to
# Transparent.
my $legendBox = $c->addLegend(270, 30, 0, "arialbi.ttf", 10);
$legendBox->setAlignment($perlchartdir::TopCenter);
$legendBox->setBackground($perlchartdir::Transparent, $perlchartdir::Transparent);

# Add a title to the chart using 18 point Times Bold Itatic font.
$c->addTitle("Parametric Curve Fitting", "timesbi.ttf", 18);

# Add titles to the axes using 12 pts Arial Bold Italic font
$c->yAxis()->setTitle("Axis Title Placeholder", "arialbi.ttf", 12);
$c->xAxis()->setTitle("Axis Title Placeholder", "arialbi.ttf", 12);

# Set the axes line width to 3 pixels
$c->yAxis()->setWidth(3);
$c->xAxis()->setWidth(3);

# Add a scatter layer using (dataX0, dataY0)
$c->addScatterLayer($dataX0, $dataY0, "Polynomial", $perlchartdir::GlassSphere2Shape,
    11, 0xff0000);

# Add a degree 2 polynomial trend line layer for (dataX0, dataY0)
my $trend0 = $c->addTrendLayer2($dataX0, $dataY0, 0xff0000);
$trend0->setLineWidth(3);
$trend0->setRegressionType(perlchartdir::PolynomialRegression(2));

# Add a scatter layer for (dataX1, dataY1)
$c->addScatterLayer($dataX1, $dataY1, "Exponential",
    $perlchartdir::GlassSphere2Shape, 11, 0x00aa00);

# Add an exponential trend line layer for (dataX1, dataY1)
my $trend1 = $c->addTrendLayer2($dataX1, $dataY1, 0x00aa00);
$trend1->setLineWidth(3);
$trend1->setRegressionType($perlchartdir::ExponentialRegression);

# Add a scatter layer using (dataX2, dataY2)
$c->addScatterLayer($dataX2, $dataY2, "Logarithmic",
    $perlchartdir::GlassSphere2Shape, 11, 0x0000ff);

# Add a logarithmic trend line layer for (dataX2, dataY2)
my $trend2 = $c->addTrendLayer2($dataX2, $dataY2, 0x0000ff);
$trend2->setLineWidth(3);
$trend2->setRegressionType($perlchartdir::LogarithmicRegression);

# Output the chart
binmode(STDOUT);
print "Content-type: image/png\n\n";
print $c->makeChart2($perlchartdir::PNG);