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color

property_to_color(prop, cmap='viridis', **kwargs)

Convert a scalar array of property values to colors, given a provided color map (or property name).

Parameters:

Name Type Description Default
prop array_like

the scalar array of property values

 required
cmap str

the color map name or property name

 'viridis'
vmin float

the minimum value of the property color scale

 required
vmax float

the maximum value of the property color scale

 required
kwargs dict

optional keyword arguments

 {}

Returns:

Name Type Description
array_like

the array of color values for the given property
Source code in chmpy/util/color.py 
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def property_to_color(prop, cmap="viridis", **kwargs):
    """
    Convert a scalar array of property values to colors,
    given a provided color map (or property name).

    Args:
        prop (array_like): the scalar array of property values
        cmap (str): the color map name or property name
        vmin (float): the minimum value of the property color scale
        vmax (float): the maximum value of the property color scale
        kwargs (dict): optional keyword arguments

    Returns:
        array_like: the array of color values for the given property
    """
    from matplotlib import colormaps

    colormap = colormaps[kwargs.get("colormap", DEFAULT_COLORMAPS.get(cmap, cmap))]

    norm = None
    vmin = kwargs.get("vmin", prop.min())
    vmax = kwargs.get("vmax", prop.max())
    midpoint = kwargs.get(
        "midpoint",
        max(min(0.0, vmax - 0.01), vmin + 0.01) if cmap in ("d_norm", "esp") else None,
    )
    if midpoint is not None:
        try:
            from matplotlib.colors import TwoSlopeNorm
        except ImportError:
            from matplotlib.colors import DivergingNorm as TwoSlopeNorm
        assert vmin <= midpoint, f"vmin={vmin} midpoint={midpoint}"
        assert vmax >= midpoint, f"vmin={vmax} midpoint={midpoint}"
        norm = TwoSlopeNorm(vmin=vmin, vcenter=midpoint, vmax=vmax)
        prop = norm(prop)
        return colormap(prop)
    else:
        import numpy as np

        prop = np.clip(prop, vmin, vmax) - vmin
        return colormap(prop)