plslabelfunc: Assign a function to use for generating custom axis labels

plslabelfunc (label_func, label_data);

This function allows a user to provide their own function to provide axis label text. The user function is given the numeric value for a point on an axis and returns a string label to correspond with that value. Custom axis labels can be enabled by passing appropriate arguments to plenv, plbox, plbox3 and similar functions.

label_func (void (*) (PLINT, PLFLT, char *, PLINT, void *), input)

This is the custom label function. In order to reset to the default labeling, set this to NULL. The labeling function parameters are, in order:

axis

This indicates which axis a label is being requested for. The value will be one of PL_X_AXIS, PL_Y_AXIS or PL_Z_AXIS.

value

This is the value along the axis which is being labeled.

label_text

The string representation of the label value.

length

The maximum length in characters allowed for label_text.

label_data (void *, input)

This parameter may be used to pass data to the label_func function.

This function is used in example 19.