pcolor(*args, shading=None, alpha=None, norm=None, cmap=None, vmin=None, vmax=None, data=None, **kwargs)
Call signature:
pcolor([X, Y,] C, **kwargs)
X and Y can be used to specify the corners of the quadrilaterals.
.. hint::
``pcolor()`` can be very slow for large arrays. In most
cases you should use the similar but much faster
`~.Axes.pcolormesh` instead. See
:ref:`Differences between pcolor() and pcolormesh()
<differences-pcolor-pcolormesh>` for a discussion of the
differences.
Masked arrays
X, Y and C may be masked arrays. If either C[i, j]
, or one of the vertices surrounding C[i, j]
(X or Y at [i, j], [i+1, j], [i, j+1], [i+1, j+1]
) is masked, nothing is plotted.
<Unimplemented 'target' '.. _axes-pcolor-grid-orientation:'>
Grid orientation
The grid orientation follows the standard matrix convention: An array C with shape (nrows, ncolumns) is plotted with the column number as X and the row number as Y.
The default antialiaseds is False if the default edgecolors\ ="none" is used. This eliminates artificial lines at patch boundaries, and works regardless of the value of alpha. If edgecolors is not "none", then the default antialiaseds is taken from patch.antialiased
. Stroking the edges may be preferred if alpha is 1, but will cause artifacts otherwise.
If given, all parameters also accept a string s
, which is interpreted as data[s]
(unless this raises an exception).
Additionally, the following arguments are allowed. They are passed along to the ~matplotlib.collections.PolyCollection
constructor:
agg_filter: a filter function, which takes a (m, n, 3) float array and a dpi value, and returns a (m, n, 3) array alpha: array-like or scalar or None animated: bool antialiased or aa or antialiaseds: bool or list of bools array: array-like or None capstyle: .CapStyle
or {'butt', 'projecting', 'round'} clim: (vmin: float, vmax: float) clip_box: .Bbox
clip_on: bool clip_path: Patch or (Path, Transform) or None cmap: .Colormap
or str or None color: color or list of rgba tuples edgecolor or ec or edgecolors: color or list of colors or 'face' facecolor or facecolors or fc: color or list of colors figure: .Figure
gid: str hatch: {'/', '\\', '|', '-', '+', 'x', 'o', 'O', '.', '*'} in_layout: bool joinstyle: .JoinStyle
or {'miter', 'round', 'bevel'} label: object linestyle or dashes or linestyles or ls: str or tuple or list thereof linewidth or linewidths or lw: float or list of floats norm: .Normalize
or None offset_transform: .Transform
offsets: (N, 2) or (2,) array-like path_effects: .AbstractPathEffect
paths: list of array-like picker: None or bool or float or callable pickradius: float rasterized: bool sizes: ndarray or None sketch_params: (scale: float, length: float, randomness: float) snap: bool or None transform: .Transform
url: str urls: list of str or None verts: list of array-like verts_and_codes: unknown visible: bool zorder: float
The color-mapped values.
The coordinates of the corners of quadrilaterals of a pcolormesh:
(X[i+1, j], Y[i+1, j]) (X[i+1, j+1], Y[i+1, j+1])
+-----+
| |
+-----+
(X[i, j], Y[i, j]) (X[i, j+1], Y[i, j+1])
Note that the column index corresponds to the x-coordinate, and the row index corresponds to y. For details, see the Notes <axes-pcolormesh-grid-orientation>
section below.
If shading='flat'
the dimensions of X and Y should be one greater than those of C, and the quadrilateral is colored due to the value at C[i, j]
. If X, Y and C have equal dimensions, a warning will be raised and the last row and column of C will be ignored.
If shading='nearest'
, the dimensions of X and Y should be the same as those of C (if not, a ValueError will be raised). The color C[i, j]
will be centered on (X[i, j], Y[i, j])
.
If X and/or Y are 1-D arrays or column vectors they will be expanded as needed into the appropriate 2D arrays, making a rectangular grid.
The fill style for the quadrilateral. Possible values:
'flat': A solid color is used for each quad. The color of the quad (i, j), (i+1, j), (i, j+1), (i+1, j+1) is given by C[i, j]
. The dimensions of X and Y should be one greater than those of C; if they are the same as C, then a deprecation warning is raised, and the last row and column of C are dropped.
'nearest': Each grid point will have a color centered on it, extending halfway between the adjacent grid centers. The dimensions of X and Y must be the same as C.
'auto': Choose 'flat' if dimensions of X and Y are one larger than C. Choose 'nearest' if dimensions are the same.
See /gallery/images_contours_and_fields/pcolormesh_grids
for more description.
A Colormap instance or registered colormap name. The colormap maps the C values to colors.
The Normalize instance scales the data values to the canonical colormap range [0, 1] for mapping to colors. By default, the data range is mapped to the colorbar range using linear scaling.
The colorbar range. If None, suitable min/max values are automatically chosen by the .Normalize
instance (defaults to the respective min/max values of C in case of the default linear scaling). It is an error to use vmin/vmax when norm is given.
The color of the edges. Defaults to 'none'. Possible values:
'none' or '': No edge.
None: patch.edgecolor
will be used. Note that currently patch.force_edgecolor
has to be True for this to work.
'face': Use the adjacent face color.
A color or sequence of colors will set the edge color.
The singular form edgecolor works as an alias.
The alpha blending value of the face color, between 0 (transparent) and 1 (opaque). Note: The edgecolor is currently not affected by this.
Whether to snap the mesh to pixel boundaries.
Create a pseudocolor plot with a non-regular rectangular grid.
imshow
If X and Y are each equidistant, :None:None:`~.Axes.imshow` can be a faster alternative.
pcolormesh
for an explanation of the differences between pcolor and pcolormesh.
The following pages refer to to this document either explicitly or contain code examples using this.
matplotlib.pyplot.pcolormesh
matplotlib.pyplot.plotting
matplotlib.pyplot.gci
Hover to see nodes names; edges to Self not shown, Caped at 50 nodes.
Using a canvas is more power efficient and can get hundred of nodes ; but does not allow hyperlinks; , arrows or text (beyond on hover)
SVG is more flexible but power hungry; and does not scale well to 50 + nodes.
All aboves nodes referred to, (or are referred from) current nodes; Edges from Self to other have been omitted (or all nodes would be connected to the central node "self" which is not useful). Nodes are colored by the library they belong to, and scaled with the number of references pointing them