Displays of histograms have several specific options, which depend on the context of the specific analysis.
For explanations of the generic menu items Print, Export to SVG File and Close Panel, follow this link.
The number of histogram bins (the subdivisions of the value axis for which the frequencies are shown) can be changed with Choose the Number of Bins. The following dialog box will appear:
The text field displays the current number of bins, which can be edited. The new value provided by the user is used as a guide for calculating the final number of bins.
For some types of histograms, the range of values shown in the histogram can be changed by the user. When one of the menu items Choose Minimum for the Value Axis or Choose Maximum for the Value Axis is selected, a dialog box like the following will appear:
The current minimum or maximum is shown in the text field, where it can be changed. The value entered by the user is used as a starting value for calculating the final maximum or minimum (this calculation also considers the range of values in the data, etc.).
For some types of histograms, it is possible to display different groups of data in different colors. The groups must be defined by a classifier variable.
If the menu item Color by Subgroups is selected, the following dialog box appears:
If the check box labeled 'Use a cassifier variable ...' is selected, a drop-down menu is activated, in which the user can select the variable that is to be used as the grouping criterion (this classifier is 'Species' in the screen shot above). A new choice of this variable eliminates any existing choice of colors.
If a classifier variable has been chosen, the list labeled 'Classes' contains all the values that occur for this classifier (in the example, these are 'Erect', 'Melan' etc.). Initially, each of these values is shown in a different color. This color will be used for the respective group in the histogram.
The colors for the groups can be changed by selecting one or more of the values in the list and then selecting a new color from the interface to the right, and then clicking the button Use Color.
Finally, click OK to use the changed colors, or Cancel to stop.