# Make some pseudo-random data.
mt_srand(1);
$data = array();
$value = 10;
for ($i = 0; $i < 500; $i++) {
$data[] = array('', $i, $value);
$value = max(0, $value + mt_rand(-9, 10));
}
# Make a color gradient array of blue:
$colors = array();
for ($b = 32; $b <= 255; $b += 2) {
$colors[] = array(0, 0, $b);
}
for ($b = 255; $b >= 32; $b -= 2) {
$colors[] = array(0, 0, $b);
}
# Use a truecolor plot image in order to get more colors.
$plot = new PHPlot_truecolor(800, 600);
$plot->SetImageBorderType('plain');
// Improves presentation in the manual
$plot->SetPlotType('thinbarline');
$plot->SetDataType('data-data');
$plot->SetDataValues($data);
$plot->SetLineWidths(2);
$plot->SetDataColors($colors);
$plot->SetXTickPos('none');
$plot->SetPlotAreaWorld(0, 0, 500, NULL);
$plot->SetTitle('Meaningless Data with Color Gradient');
# Establish the function 'getcolor' as a data color selection callback.
$plot->SetCallback('data_color', 'getcolor');
$plot->DrawGraph();
// Y range
$max_z = 100;
// Z range
$alpha = 80;
// Alpha (transparency) for data colors. 0=opaque, 127=clear.
$data = array();
mt_srand(1);
for ($x = 0; $x < $n_x; $x++) {
$row = array('', mt_rand(0, $max_x - 1));
// Label and X value
for ($y = 0; $y < $n_y; $y++) {
$row[] = mt_rand(0, $max_y - 1);
// Y value
$row[] = mt_rand(0, $max_z - 1);
// Z value
}
$data[] = $row;
}
$legend = array();
for ($y = 0; $y < $n_y; $y++) {
$legend[] = "Data Set {$y}";
}
$p = new PHPlot_truecolor(800, 600);
$p->SetTitle("Bubble Plot - Random data, Truecolor\nTranslucent (alpha={$alpha}) bubbles");
$p->SetDataColors(NULL, NULL, $alpha);
$p->SetDataType('data-data-xyz');
$p->SetPlotType('bubbles');
$p->SetDataValues($data);
$p->SetLegend($legend);
$p->SetPlotAreaWorld(0, 0, $max_x, $max_y);
$p->DrawGraph();
