CPlot supports these types of parameters:
To create: Use the + button in the Parameters box.
To delete: Select Delete from the context menu (click & wait or right mouse button on a parameter name).
To edit: Doubleclick or context menu.
To set the parameter's value, use either the sliders or enter any value into the matching text field. The text field will parse any entered formula but the parameter stores only the current value, so if a parameter is set to sin(a), it will not update when the value of a changes. Computed parameters can be defined as custom functions with no arguments.
In the creation/editing dialog, Min/Max define the valid range for re(parameter), iMin/iMax are for the range of im(parameter) and rMax is for abs(parameter).
The sliders work differently, depending on whether or not the range of a parameter is compact. If it is - i.e. min and max are set for a real parameter or either rmax or all the r/i min/max are set for a complex parameter - then they map that range to their range, otherwise they continuously translate the value.