Oct 14, 2020 · Oct 10, 2020
diff --git a/lib/matplotlib/colors.py b/lib/matplotlib/colors.py
    After ::

        @_make_norm_from_scale(scale_cls)
        classbase_norm_cls(Normalize):
        classnorm_cls(Normalize):
            ...

    *base_norm_cls* is filled with methods so that normalization computations
    are forwarded to *scale_cls* (i.e., *scale_cls* is the scale that would be
    used for the colorbar of a mappable normalized with *base_norm_cls*).

    The constructor signature of *base_norm_cls* is derived from the
    constructor signature of *scale_cls*, but can be overridden using *init*
    (a callable which is *only* used for its signature).
    *norm_cls* is filled with methods so that normalization computations are
    forwarded to *scale_cls* (i.e., *scale_cls* is the scale that would be used
    for the colorbar of a mappable normalized with *norm_cls*).

    If *init* is not passed, then the constructor signature of *norm_cls*
    will be ``norm_cls(vmin=None, vmax=None, clip=False)``; these three
    parameters will be forwarded to the base class (``Normalize.__init__``),
    and a *scale_cls* object will be initialized with no arguments (other than
    a dummy axis).

    If the *scale_cls* constructor takes additional parameters, then *init*
    should be passed to `_make_norm_from_scale`.  It is a callable which is
    *only* used for its signature.  First, this signature will become the
    signature of *norm_cls*.  Second, the *norm_cls* constructor will bind the
    parameters passed to it using this signature, extract the bound *vmin*,
    *vmax*, and *clip* values, pass those to ``Normalize.__init__``, and
    forward the remaining bound values (including any defaults defined by the
    signature) to the *scale_cls* constructor.
    """

    if base_norm_cls is None:
        return functools.partial(_make_norm_from_scale, scale_cls, init=init)

    if init is None:
        def init(vmin=None, vmax=None, clip=False): pass
 init_signature = inspect.signature(init)
 bound_init_signature = inspect.signature(init)

    class Norm(base_norm_cls):

        def __init__(self, *args, **kwargs):
            ba =init_signature.bind(*args, **kwargs)
            ba =bound_init_signature.bind(*args, **kwargs)
            ba.apply_defaults()
            super().__init__(
                **{k: ba.arguments.pop(k) for k in ["vmin", "vmax", "clip"]})
    Norm.__name__ = base_norm_cls.__name__
    Norm.__qualname__ = base_norm_cls.__qualname__
    Norm.__module__ = base_norm_cls.__module__
    Norm.__init__.__signature__ = bound_init_signature.replace(parameters=[
        inspect.Parameter("self", inspect.Parameter.POSITIONAL_OR_KEYWORD),
        *bound_init_signature.parameters.values()])
    return Norm
Original file line number	Diff line number	Diff line change
Expand Up		@@ -1262,29 +1262,40 @@ def _make_norm_from_scale(scale_cls, base_norm_cls=None, *, init=None):
		After ::

		@_make_norm_from_scale(scale_cls)
		classbase_norm_cls(Normalize):
		classnorm_cls(Normalize):
		...

		base_norm_cls is filled with methods so that normalization computations
		are forwarded to scale_cls (i.e., scale_cls is the scale that would be
		used for the colorbar of a mappable normalized with base_norm_cls).

		The constructor signature of base_norm_cls is derived from the
		constructor signature of scale_cls, but can be overridden using init
		(a callable which is only used for its signature).
		norm_cls is filled with methods so that normalization computations are
		forwarded to scale_cls (i.e., scale_cls is the scale that would be used
		for the colorbar of a mappable normalized with norm_cls).

		If init is not passed, then the constructor signature of norm_cls
		will be ``norm_cls(vmin=None, vmax=None, clip=False)``; these three
		parameters will be forwarded to the base class (``Normalize.__init__``),
		and a scale_cls object will be initialized with no arguments (other than
		a dummy axis).

		If the scale_cls constructor takes additional parameters, then init
		should be passed to `_make_norm_from_scale`. It is a callable which is
		only used for its signature. First, this signature will become the
		signature of norm_cls. Second, the norm_cls constructor will bind the
		parameters passed to it using this signature, extract the bound vmin,
		vmax, and clip values, pass those to ``Normalize.__init__``, and
		forward the remaining bound values (including any defaults defined by the
		signature) to the scale_cls constructor.
		"""

		if base_norm_cls is None:
		return functools.partial(_make_norm_from_scale, scale_cls, init=init)

		if init is None:
		def init(vmin=None, vmax=None, clip=False): pass
		init_signature = inspect.signature(init)
		bound_init_signature = inspect.signature(init)

		class Norm(base_norm_cls):

		def __init__(self, args, *kwargs):
		ba =init_signature.bind(args, *kwargs)
		ba =bound_init_signature.bind(args, *kwargs)
		ba.apply_defaults()
		super().__init__(
		**{k: ba.arguments.pop(k) for k in ["vmin", "vmax", "clip"]})
Expand DownExpand Up		@@ -1329,6 +1340,9 @@ def inverse(self, value):
		Norm.__name__ = base_norm_cls.__name__
		Norm.__qualname__ = base_norm_cls.__qualname__
		Norm.__module__ = base_norm_cls.__module__
		Norm.__init__.__signature__ = bound_init_signature.replace(parameters=[
		inspect.Parameter("self", inspect.Parameter.POSITIONAL_OR_KEYWORD),
		*bound_init_signature.parameters.values()])
		return Norm


Expand Down