Vector layer histogram visual example

Author: hefniraera

docs/user_manual/processing_algs/qgis/img/vector_layer_histogram.png

@@ -592,6 +592,11 @@ Generates a histogram with the values of the attribute of a vector layer.
 
 The attribute to use for computing the histogram must be numeric.
 
+.. figure:: img/vector_layer_histogram.png
+   :align: center
+
+   Example of vector layer histogram
+
 Parameters
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