pyissm.plot.colormaps

Custom colormaps for ISSM visualizations.

Ported from ISSM src/m/plot/colormaps/

Functions

blueyellowred([n])

Blue-Yellow-Red colormap.

demmap(ncolors, minZ, maxZ[, colorscheme])

DEM colormap concatenating sea and land colors.

get_colormap(name[, alpha])

Get a matplotlib colormap by name, including ISSM custom maps.

ibcao(nsea, nland)

IBCAO colormap for polar regions.

landcolor([n])

Land colormap (green to brown).

seacolor([n])

Sea colormap (deep navy to pale blue).

truncate_colormap(cmap[, minval, maxval, n])

Truncate a colormap within normalized limits [minval, maxval].
pyissm.plot.colormaps.blueyellowred(n=256)

Blue-Yellow-Red colormap.

Ported from MATLAB blueyellowred.m. Runs from white through blue-purple, yellow, and into deep red.

Parameters:

n (int) – Number of color levels. Default 256.

Returns:

RGB color array.

Return type:

np.ndarray, shape (3, n)

pyissm.plot.colormaps.demmap(ncolors, minZ, maxZ, colorscheme='dem')

DEM colormap concatenating sea and land colors.

Parameters:

  • ncolors (int) – Total number of colors.

  • minZ (float) – Minimum elevation (negative for seafloor).

  • maxZ (float) – Maximum elevation.

  • colorscheme (str) – ‘dem’ (default) or ‘ibcao’.

Return type:

matplotlib.colors.ListedColormap

Examples

cmap = demmap(50, -300, 1200) cmap = demmap(50, -300, 1200, ‘ibcao’)

pyissm.plot.colormaps.get_colormap(name, alpha=1)

Get a matplotlib colormap by name, including ISSM custom maps.

Supported custom names:

‘Rignot’ — modified HSV rainbow scaled by velocity ‘demmap(n,z0,z1)’ — calls demmap(n, z0, z1) Any standard matplotlib colormap name

Parameters:

  • name (str or matplotlib.colors.Colormap) – Colormap name or existing colormap object.

  • alpha (float) – Exponent used for ‘Rignot’ colormap. Default 1.

Return type:

matplotlib.colors.Colormap

pyissm.plot.colormaps.ibcao(nsea, nland)

IBCAO colormap for polar regions.

Parameters:

  • nsea (int) – Number of sea colors.

  • nland (int) – Number of land colors.

Returns:

RGB color array.

Return type:

np.ndarray, shape (nsea + nland, 3)

pyissm.plot.colormaps.landcolor(n=256)

Land colormap (green to brown).

Parameters:

n (int) – Number of color levels. Default 256.

Returns:

RGB color array.

Return type:

np.ndarray, shape (3, n)

pyissm.plot.colormaps.seacolor(n=256)

Sea colormap (deep navy to pale blue).

Parameters:

n (int) – Number of color levels. Default 256.

Returns:

RGB color array.

Return type:

np.ndarray, shape (3, n)

pyissm.plot.colormaps.truncate_colormap(cmap, minval=0.0, maxval=1.0, n=100)

Truncate a colormap within normalized limits [minval, maxval].

Parameters:

  • cmap (str or matplotlib.colors.Colormap)

  • minval (float) – Lower bound, normalized [0, 1].

  • maxval (float) – Upper bound, normalized [0, 1].

  • n (int) – Number of levels in the new colormap.

Return type:

matplotlib.colors.LinearSegmentedColormap

Example

cmap = truncate_colormap(‘viridis’, 0.2, 0.8)