@lujakob,
You can set the distance between data points same as width of the of the data points by setting dataPointWidth dynamically as shown in the code snippet below.
chart.set("dataPointWidth",Math.ceil(chart.axisX[0].bounds.width/chart.data[0].dataPoints.length / 2),true);
Please take a look at this JSFiddle for the working example on the same.
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Sachin Bisht
Team CanvasJS