ChartDirector 6.0 (C++ Edition)

Binary Data Series




This example demonstrates a chart representing binary data series.

A binary data series is a series with elements that can only assume two values. In this example, 0 and 1 are used to represent the two values.

There are plenty of methods to represent binary data series in a chart. In this example, three methods are demonstrated.

Source Code Listing

[The following code is available in "cppdemo/binaryseries". A MFC version of the code is available in "mfcdemo/mfcdemo" (Windows edition only). A QT version of the code is available in "qtdemo/qtdemo".]
#include "chartdir.h"

int main(int argc, char *argv[])
{
    // The data for the chart
    double dataY[] = {1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 1};
    double dataX[] = {Chart::chartTime(2008, 7, 1, 0, 0, 0), Chart::chartTime(2008, 7, 1, 2, 17, 2),
        Chart::chartTime(2008, 7, 1, 8, 5, 30), Chart::chartTime(2008, 7, 1, 10, 54, 10),
        Chart::chartTime(2008, 7, 1, 15, 40, 0), Chart::chartTime(2008, 7, 1, 18, 22, 20),
        Chart::chartTime(2008, 7, 1, 22, 17, 14), Chart::chartTime(2008, 7, 2, 2, 55, 50),
        Chart::chartTime(2008, 7, 2, 8, 17, 14), Chart::chartTime(2008, 7, 2, 11, 55, 50),
        Chart::chartTime(2008, 7, 2, 13, 17, 14), Chart::chartTime(2008, 7, 2, 17, 55, 50),
        Chart::chartTime(2008, 7, 2, 20, 17, 14), Chart::chartTime(2008, 7, 3, 0, 0, 0)};

    // In this example, we only use position 1, 3, 5 for the data series. Positions 0, 2, 4, 6 are
    // empty and serve as gaps.
    const char *labels[] = {"", "ON Only Filling", "",
        "<*font,color=cc2200*>ON<*/font*> / <*font,color=00aa22*>OFF<*/font*> Filling", "",
        "Logic Line", ""};

    // Create a XYChart object of size 600 x 180 pixels
    XYChart *c = new XYChart(600, 180);

    // Add a title to the chart using 10 points Arial Bold font. Set top/bottom margins to 12
    // pixels.
    TextBox *title = c->addTitle("Binary Data Series Demonstration", "arialbd.ttf", 10);

    // Tentatively set the plotarea at (100, 30) and of size 470 x 120 pixels. Use transparent
    // border. Use grey (888888) solid line and light grey (ccccc) dotted line as major and minor
    // vertical grid lines.
    c->setPlotArea(100, 30, 470, 120, -1, -1, Chart::Transparent)->setGridColor(Chart::Transparent,
        0x888888, Chart::Transparent, c->dashLineColor(0xcccccc, Chart::DotLine));

    // Set axes to transparent
    c->xAxis()->setColors(Chart::Transparent);
    c->yAxis()->setColors(Chart::Transparent);

    // Set the y axis labels
    c->yAxis()->setLabels(StringArray(labels, (int)(sizeof(labels) / sizeof(labels[0]))));

    // Set y-axis label style to 8pt Arial Bold
    c->yAxis()->setLabelStyle("arialbd.ttf", 8);

    // Set x-axis major and minor tick density to 50 and 5 pixels. ChartDirector auto-scaling will
    // use this as the guideline when putting ticks on the x-axis.
    c->xAxis()->setTickDensity(50, 5);

    // Use "<*font=Arial Bold*>{value|mmm dd}" for the first label of an hour, and "{value|hh:nn}"
    // for all other labels.
    c->xAxis()->setMultiFormat(Chart::StartOfDayFilter(), "<*font=arialbd.ttf*>{value|mmm dd}",
        Chart::AllPassFilter(), "{value|hh:nn}");

    //
    // A Logic Line can be achieved using a StepLineLayer in ChartDirector
    //

    // Shift the data by 4.5, so instead of 0 - 1, it is now 4.5 to 5.5, or fluctuate around the y =
    // 5 (Logic Line label) position.
    ArrayMath shiftedLine0 = ArrayMath(DoubleArray(dataY, (int)(sizeof(dataY) / sizeof(dataY[0])))
        ).add(4.5);

    // Add step lines using the original and the reversed data
    StepLineLayer *layer0 = c->addStepLineLayer(shiftedLine0, 0x0000ff);
    layer0->setXData(DoubleArray(dataX, (int)(sizeof(dataX) / sizeof(dataX[0]))));

    //
    // To perform ON/OFF filling, we draw the logic line, and its reverse, and fill the region in
    // between
    //

    // Shift the data by 2.5, so instead of 0 - 1, it is now 2.5 to 3.5, or fluctuate around the y =
    // 3 (ON/OFF Filing label) position.
    ArrayMath shiftedLine1 = ArrayMath(DoubleArray(dataY, (int)(sizeof(dataY) / sizeof(dataY[0])))
        ).add(2.5);
    // Reverse the data, so the 0 becomes 1 and 1 becomes 0, and shift it as well.
    ArrayMath reverseShiftedLine1 = ArrayMath(DoubleArray(dataY, (int)(sizeof(dataY) / sizeof(dataY[
        0])))).mul(-1).add(3.5);

    // Add step lines using the original and the reversed data
    StepLineLayer *layer1 = c->addStepLineLayer(shiftedLine1, Chart::Transparent);
    layer1->addDataSet(reverseShiftedLine1, Chart::Transparent);
    layer1->setXData(DoubleArray(dataX, (int)(sizeof(dataX) / sizeof(dataX[0]))));

    // Fill the region between the two step lines with green (00aa22) or red (cc2200), depending on
    // whether the original or the reserve is higher.
    c->addInterLineLayer(layer1->getLine(0), layer1->getLine(1), 0x00aa22, 0xcc2200);

    //
    // The ON Only filling is the same as ON/OFF filling, except the OFF filling color is
    // transparent
    //

    // Shift the data by 0.5, so instead of 0 - 1, it is now 0.5 to 1.5, or fluctuate around the y =
    // 1 (ON Only Filing label) position.
    ArrayMath shiftedLine2 = ArrayMath(DoubleArray(dataY, (int)(sizeof(dataY) / sizeof(dataY[0])))
        ).add(0.5);
    // Reverse the data, so the 0 becomes 1 and 1 becomes 0, and shift it as well.
    ArrayMath reverseShiftedLine2 = ArrayMath(DoubleArray(dataY, (int)(sizeof(dataY) / sizeof(dataY[
        0])))).mul(-1).add(1.5);

    // Add step lines using the original and the reversed data
    StepLineLayer *layer2 = c->addStepLineLayer(shiftedLine2, Chart::Transparent);
    layer2->addDataSet(reverseShiftedLine2, Chart::Transparent);
    layer2->setXData(DoubleArray(dataX, (int)(sizeof(dataX) / sizeof(dataX[0]))));

    // Fill the region between the two step lines with green (00aa22) or transparent, depending on
    // whether the original or the reserve is higher.
    c->addInterLineLayer(layer2->getLine(0), layer2->getLine(1), 0x00aa22, Chart::Transparent);

    // Adjust the plot area size, such that the bounding box (inclusive of axes) is 10 pixels from
    // the left edge, 10 pixels  below the title, 30 pixels from the right edge, and 10 pixels above
    // the bottom edge.
    c->packPlotArea(10, title->getHeight() + 10, c->getWidth() - 30, c->getHeight() - 10);

    // Output the chart
    c->makeChart("binaryseries.png");

    //free up resources
    delete c;
    return 0;
}