PlasmaCalcs.plotting.plot_tools.colors.Colormap

class PlasmaCalcs.plotting.plot_tools.colors.Colormap(*args_super, under=NO_VALUE, over=NO_VALUE, bad=NO_VALUE, **kw_super)

Bases: BaseColormap, ListedColormap

matplotlib.colors.ListedColormap with some extra methods.

Especially helpful options include:

self.at(fractions) –> new Colormap with only the colors at fractions
self.shrink(min, max) –> new Colormap but smaller range of colors
self + other –> new Colormap from concatenating lists of colors

under: NO_VALUE, None, str, or other specifier for a color.: the color for low out-of-range values.

if provided (not NO_VALUE), sets self.under = under.
over: NO_VALUE, None, str, or other specifier for a color.: the color for high out-of-range values.

if provided (not NO_VALUE), sets self.over = over.
bad: NO_VALUE, None, str, or other specifier for a color.: the color for masked values.

if provided (not NO_VALUE), sets self.bad = bad.

see help(mpl.colors.ListedColormap) for more details on __init__.

__init__(*args_super, under=NO_VALUE, over=NO_VALUE, bad=NO_VALUE, **kw_super)

Parameters

———-

namestr: The name of the colormap.
Nint: The number of RGB quantization levels.

Methods

`__init__`(*args_super[, under, over, bad])
`at`(fractions)
`copy`()
`expand`([min, max])
`from_cmap`(cmap, **kw)
`get_bad`()
`get_cmap`([based_on, N, colors, name, ...])
`get_extremes`()
`get_over`()
`get_under`()
`is_gray`()
`resampled`(N, **kw__super)
`reversed`([name])
`set_bad`([color, alpha])
`set_extremes`(*[, under, over, bad])
`set_over`([color, alpha])
`set_under`([color, alpha])
`shrink`([min, max, N])
`with_bad`(bad)
`with_extremes`(*[, under, over, bad])
`with_over`(over)
`with_under`(under)

Attributes

`bad`
`colorbar_extend`
`colorbar_extend_settings`
`extremes`
`over`
`under`

at(fractions): return copy of self but only keep colors at self(fractions).

E.g. self.at([0.1, 0.5, 0.9]) gives cmap with N=3,

and colors at 10%, 50%, and 90% of the way along self.

property bad: the color for masked values. Use self.bad=None to restore default.

property colorbar_extend: defaults instructions for whether to extend colorbars using this colormap.

One of the following values:

‘neither’ –> do not extend colorbar.

‘both’ –> extend colorbar in both directions.

‘min’ –> extend colorbar in the direction of the minimum value.

‘max’ –> extend colorbar in the direction of the maximum value.

When setting self.colorbar_extend=value, value can be:

str –> use value (must be ‘neither’, ‘both’, ‘min’, or ‘max’).

True –> use ‘both’

False –> use ‘neither’

property colorbar_extend_settings: the current dict(under=bool, over=bool) corresponding to colorbar_extend.

copy(): Return a copy of the colormap.

expand(min=0, max=1): return copy of self but larger, filling pre-min with min and post-max with max.

E.g. self.expand(-0.3, 1.2) has N = 1.5 * self.N,

with first 3/15 colors being min, and last 2/15 colors being max.

property extremes: (under, over, bad), as a ColormapExtremes namedtuple.

setting self.extremes = value is possible, but to avoid ambiguity:

value must have keys “under”, “over”, and/or “bad”,

or attributes “under”, “over”, and/or “bad”.

e.g. self.extremes = dict(under=’blue’)

(equivalent to self.under=’blue’)

Use None to reset to default, e.g. self.extremes = None,

(equivalent to self.under=None, self.over=None, self.bad=None)

or for any keys, e.g. self.extremes = dict(under=’blue’, over=None)

(equivalent to self.under=’blue’, self.over=None, but not adjusting self.bad)

classmethod from_cmap(cmap, **kw)

return Colormap from cmap.

cmap: Colormap or matplotlib.colors.ListedColormap: [TODO] or matplotlib.colors.LinearSegmentedColormap

additional kwargs go to cls.__new__ and cls.__init__.

get_bad(): Get the color for masked values.

classmethod get_cmap(based_on=None, N=None, *, colors=None, name=None, reversed=False, under=NO_VALUE, over=NO_VALUE, bad=NO_VALUE, **kw_init)

Get a Colormap instance, possibly based on a default colormap from matplotlib.

based_on: matplotlib.colors.Colormap, str, or None: the colormap to base the result on.

None –> use the default colormap (from matplotlib rc; image.cmap)

(or, if colors are provided, use colors to make a new colormap instead).

str –> use the colormap with this name from matplotlib.

(or, if colors are provided, set this to the name of the new colormap).

Colormap –> base the result on this colormap.

(mutually exclusive with providing a value for colors)
N: None or int: number of colors to use.

None –> use the number of colors in based_on.

int –> resample to this many colors.
colors: None or array-like of colors: None –> ignore this parameter

array-like –> provide these to make a new Colormap.

(mutually exclusive with providing a Colormap for based_on)
name: None or str: the name for the new Colormap.

if None, infer name from the old colormap or the provided value of based_on.
reversed: bool: whether to return result.reversed(), instead.
under: NO_VALUE, None, str, or other specifier for a color.: the color for low out-of-range values.

if provided (not NO_VALUE), sets result.under = under.
over: NO_VALUE, None, str, or other specifier for a color.: the color for high out-of-range values.

if provided (not NO_VALUE), sets result.over = over.
bad: NO_VALUE, None, str, or other specifier for a color.: the color for masked values.

if provided (not NO_VALUE), sets result.bad = bad.

additional kwargs are passed to cls(…) when creating the result.

get_extremes(): return (under, over, bad) colors, as a ColormapExtremes namedtuple.

get_over(): Get the color for high out-of-range values.

get_under(): Get the color for low out-of-range values.

is_gray(): Return whether the colormap is grayscale.

property over: the color for high out-of-range values.

when setting self.over = value, value can be:

str –> use this color.

None or bool –> use the default color (top of the colormap).

if not None, also sets self.colorbar_extend_settings[‘over’],

to True if (str or True), else False.

resampled(N, **kw__super): return a copy of self, resampled to size N.

reversed(name=None, **kw__super): return a copy of self, with reversed colors.

if name is None, use name = self.name + “_r”.

set_bad(color=None, alpha=None, **kw_super): set the color for masked values. See help(type(self).bad) for details.

set_extremes(*, under=NO_VALUE, over=NO_VALUE, bad=NO_VALUE): set under, over, bad colors, based on keywords.

see help(type(self).extremes) for details.

set_over(color=None, alpha=None, **kw_super): set the color for high out-of-range values. See help(type(self).over) for details.

set_under(color=None, alpha=None, **kw_super): set the color for low out-of-range values. See help(type(self).under) for details.

shrink(min=0, max=1, N=None)

return copy of self but only keep colors between min and max.

E.g. self.shrink(0.2, 0.7) only keeps colors between 20% and 70% of the way along self.

N: None or int: number of colors to use for the result.

None –> keep similar spacing of colors as in self

property under: the color for low out-of-range values.

when setting self.under = value, value can be:

str –> use this color.

None –> use the default color (bottom of the colormap).

if not None, also sets self.colorbar_extend_settings[‘under’],

to True if (str or True), else False.

with_bad(bad): return a copy of self, with new color for bad.

with_extremes(*, under=NO_VALUE, over=NO_VALUE, bad=NO_VALUE): return a copy of self, with new colors for under, over, and/or bad.

see help(type(self).extremes) for details.

with_over(over): return a copy of self, with new color for over.

with_under(under): return a copy of self, with new color for under.