PercentBarChart Example▲

A percent bar chart shows the data in sets as a percentage of all sets per category.

Creating percent bar charts is just like creating a regular bar chart, except that for a percent bar charts, we use the QPercentBarSeries api instead of QBarSeries. Also, in the bar chart we used the nice numbers algorithm to make the y-axis numbering look better. With the percent bar chart there is no need for that, because the maximum y-axis value is always 100.

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Running the Example▲

To run the example from Qt Creator, open the Welcome mode and select the example from Examples. For more information, visit Building and Running an Example.

Creating Percent Bar Charts▲

The barsets are used in same way in all barcharts. To illustrate the difference between various barcharts, we use the same data in all examples. The data visualized by the bar chart is defined by QBarSet instances. Here we create the sets and append data to them. The data is appended here with the << operator. Alternatively the append method could be used.

 
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    QBarSet *set0 = new QBarSet("Jane");
    QBarSet *set1 = new QBarSet("John");
    QBarSet *set2 = new QBarSet("Axel");
    QBarSet *set3 = new QBarSet("Mary");
    QBarSet *set4 = new QBarSet("Samantha");

    *set0 &lt;&lt; 1 &lt;&lt; 2 &lt;&lt; 3 &lt;&lt; 4 &lt;&lt; 5 &lt;&lt; 6;
    *set1 &lt;&lt; 5 &lt;&lt; 0 &lt;&lt; 0 &lt;&lt; 4 &lt;&lt; 0 &lt;&lt; 7;
    *set2 &lt;&lt; 3 &lt;&lt; 5 &lt;&lt; 8 &lt;&lt; 13 &lt;&lt; 8 &lt;&lt; 5;
    *set3 &lt;&lt; 5 &lt;&lt; 6 &lt;&lt; 7 &lt;&lt; 3 &lt;&lt; 4 &lt;&lt; 5;
    *set4 &lt;&lt; 9 &lt;&lt; 7 &lt;&lt; 5 &lt;&lt; 3 &lt;&lt; 1 &lt;&lt; 2;

We create the series and append the barsets to it. The series takes ownership of the barsets. The series groups the data from sets to categories. The first values of each set are grouped together in the first category, the second values in the second category etc.

 
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    QPercentBarSeries *series = new QPercentBarSeries();
    series-&gt;append(set0);
    series-&gt;append(set1);
    series-&gt;append(set2);
    series-&gt;append(set3);
    series-&gt;append(set4);