chaco.scales_tick_generator module

Defines the ScalesTickGenerator class.

class chaco.scales_tick_generator.ScalesTickGenerator

Bases: chaco.ticks.AbstractTickGenerator

get_ticks(data_low, data_high, bounds_low, bounds_high, interval, use_endpoints=False, scale=None)

Returns a list of ticks points in data space.

Parameters

  • data_low (float) – The actual minimum and maximum of index values of the entire dataset.

  • data_high (float) – The actual minimum and maximum of index values of the entire dataset.

  • bounds_low ("auto", "fit", float) – The range for which ticks should be generated.

  • bounds_high ("auto", "fit", float) – The range for which ticks should be generated.

  • interval ("auto", float) – If the value is a positive number, it specifies the length of the tick interval; a negative integer specifies the number of tick intervals; ‘auto’ specifies that the number and length of the tick intervals are automatically calculated, based on the range of the axis.

  • use_endpoints (Boolean) – If True, the lower and upper bounds of the data are used as the lower and upper end points of the axis. If False, the end points might not fall exactly on the bounds.

  • scale ('linear' or 'log') – The type of scale the ticks are for.

Returns

tick_list – Where ticks are to be placed.

Return type

array of floats

Example

If the range of x-values in a line plot span from -15.0 to +15.0, but the plot is currently displaying only the region from 3.1 to 6.83, and the user wants the interval to be automatically computed to be some nice value, then call get_ticks() thusly:

get_ticks(-15.0, 15.0, 3.1, 6.83, "auto")

A reasonable return value in this case would be:

[3.5, 4.0, 4.5, 5.0, 5.5, 6.0, 6.5]
get_ticks_and_labels(data_low, data_high, bounds_low, bounds_high, orientation='h')