Colormap functions

Overview

The plotpy.mathutils.colormap module contains definition of common colormaps and tools to manipulate and create them.

The following functions are available:

• get_cmap(): get a colormap from its name

• cmap_exists(): check if a colormap exists

• add_cmap(): add a colormap to the list of available colormaps

• build_icon_from_cmap(): build an icon representing the colormap

• build_icon_from_cmap_name(): build an icon representing the colormap from its name

Reference

plotpy.mathutils.colormap.get_cmap(cmap_name: str) → EditableColormap

Returns the colormap with the given name from the ALL_COLORMAPS global variable. If the colormap is not found, returns the DEFAULT colormap.

Parameters:

cmap_name – colormap name to search in ALL_COLORMAPS. All keys in ALL_COLORMAPS are lower case, so the given name is also lowered.

Returns:

A CustomQwtLinearColormap instance corresponding to the given name, if no colormap is found, returns the DEFAULT colormap.

plotpy.mathutils.colormap.cmap_exists(cmap_name: str, cmap_dict: Dict[str, EditableColormap] | None = None) → bool

Returns True if the colormap with the given name exists in the given colormap dictionary, False otherwise. If no dictionary is given, the ALL_COLORMAPS global variable is used.

Parameters:

• cmap_name – colormap name to search in given colormap dictionnary. All keys in the dictionary are lower case, so the given name is also lowered.

• cmap_dict – colormap dictionnary to search in. If None, ALL_COLORMAPS is used.

Returns:

True if the colormap exists, False otherwise.

plotpy.mathutils.colormap.add_cmap(cmap: EditableColormap) → None

Adds the given colormap to both ALL_COLORMAPS and CUSTOM_COLORMAPS global variables.

Parameters:

cmap – colormap to add

plotpy.mathutils.colormap.build_icon_from_cmap(cmap: EditableColormap, width: int = 16, height: int = 7, orientation: Literal['h', 'v'] = 'h', margin: int = 0) → QIcon

Builds an icon representing the colormap

Parameters:

• cmap – colormap

• width – icon width

• height – icon height

• orientation – orientation of the colormap in the icon. Can be “h” for horizontal or “v” for vertical

• margin – margin around the colormap in the icon. Beware that the margin is included in the given icon size. For example, if margin is 1 and width is 16, the actual colormap width will be 14 (16 - 2 * 1). This was done to prevent interpolation on display.

plotpy.mathutils.colormap.build_icon_from_cmap_name(cmap_name: str, width: int = 16, height: int = 7, orientation: Literal['h', 'v'] = 'h', margin: int = 0) → QIcon

Builds an QIcon representing the colormap from the colormap name found in ALL_COLORMAPS global variable.

Parameters:

• cmap_name – colormap name to search in ALL_COLORMAPS

• width – icon width

• height – icon height

• orientation – orientation of the colormap in the icon. Can be “h” for horizontal or “v” for vertical

• margin – margin around the colormap in the icon. Beware that the margin is included in the given icon size. For example, if margin is 1 and width is 16, the actual colormap width will be 14 (16 - 2 * 1). This was done to prevent interpolation on display.

Returns:

QIcon representing the colormap