What is a Histogram Chart

It may look like a vertical Bar Chart, but histogram values are calculated internally in a much different way. You may pump some numeric data into a Column Chart, and show no gaps between the bars, but this is still not a Histogram.

Histogram Charts calculate and render the statistical distribution of your values over a number of intervals, called bins or buckets. We use by default 20 buckets, but you may change this number and get a slightly different view.

Steps to Create a Histogram Chart

Start Visual Xtractor or Data Xtractor. Connect to a database. Create or design a SQL query. Run the query and check the results.

  1. Display and enable the Chart query builder.
  2. Select one numeric column as Point ChartsHistogram.

Histogram Chart Demo Query

Look for the ready-to-use Histogram Chart generated chart query under the Queries > Demo Queries > Charts > Cartesian Charts folder. Click on the “add demo queries” command link, to make sure it’s there.

The demo chart looks more complex, as it is a mixed chart, that we will present as final custom view later on. But is is very easy to start from scratch: just pass all values from any numeric data column you may have to a Histogram selection.

Histogram Chart

Play with different values for the selected bins/buckets, which will translate into the total number of bars you want to see on the chart.

Customize your Histogram Chart

  1. Change the drawing style of your bars.
  2. Select a semi-transparent Density Plot for the exact same column values, to get a similar chart mixed with the initial Histogram.
  3. Present yet another view with a Scatter Bar on top, on the exact same values again.
  4. Switch to 3D eventually, for a nice interesting view.

Mixed Histogram Chart

Conclusion

  • Creating a Histogram Chart in Data Xtractor or Visual Xtractor is fast and immediate: just pass some numeric column values to a Histogram chart type selection, nothing more.
  • Show a semi-transparent Density Plot on the background, on the same column values.
  • Or add a horizontal Scatter Bar on top, on the same values, for yet another view.
  • All builtin powerful features of these chart type are common to most other charts: filtering series through the legend items, interactivity, monochrome or grayscale colors, rich axis and data label selections etc.
  • Switch to another builtin chart theme, or customize your own, for any possible color or other styles.