matplotlib.pyplot.tricontourf #

matplotlib.pyplot.tricontourf(*args,**kwargs)[source]#

Draw contour regions on an unstructured triangular grid.

Call signatures:

tricontourf(triangulation,z,[levels],...)tricontourf(x,y,z,[levels],*,[triangles=triangles],[mask=mask],...)

The triangular grid can be specified either by passing aTriangulationobject as the first parameter, or by passing the pointsx,y andoptionally thetriangles and amask. SeeTriangulation for anexplanation of these parameters. If neither oftriangulation ortriangles are given, the triangulation is calculated on the fly.

It is possible to passtriangles positionally, i.e.tricontourf(x,y,triangles,z,...). However, this is discouraged. For moreclarity, passtriangles via keyword argument.

Parameters:

triangulationTriangulation, optional

An already created triangular grid.

x, y, triangles, mask

Parameters defining the triangular grid. SeeTriangulation.This is mutually exclusive with specifyingtriangulation.

zarray-like

The height values over which the contour is drawn. Color-mapping iscontrolled bycmap,norm,vmin, andvmax.

Note

All values inz must be finite. Hence, nan and inf values musteither be removed orset_mask be used.

levelsint or array-like, optional

Determines the number and positions of the contour lines / regions.

If an intn, useMaxNLocator, which tries toautomatically choose no more thann+1 "nice" contour levels betweenbetween minimum and maximum numeric values ofZ.

If array-like, draw contour lines at the specified levels. The values mustbe in increasing order.

Returns:

TriContourSet

Other Parameters:

colorscolor or list ofcolor, optional

The colors of the levels, i.e., the contour regions.

The sequence is cycled for the levels in ascending order. If the sequenceis shorter than the number of levels, it is repeated.

As a shortcut, single color strings may be used in place of one-elementlists, i.e.'red' instead of['red'] to color all levels with thesame color. This shortcut does only work for color strings, not for otherways of specifying colors.

By default (valueNone), the colormap specified bycmap will be used.

alphafloat, default: 1

The alpha blending value, between 0 (transparent) and 1 (opaque).

cmapstr orColormap, default:rcParams["image.cmap"] (default:'viridis')

The Colormap instance or registered colormap name used to map scalar datato colors.

This parameter is ignored ifcolors is set.

normstr orNormalize, optional

The normalization method used to scale scalar data to the [0, 1] rangebefore mapping to colors usingcmap. By default, a linear scaling isused, mapping the lowest value to 0 and the highest to 1.

If given, this can be one of the following:

An instance ofNormalize or one of its subclasses(seeColormap normalization).
A scale name, i.e. one of "linear", "log", "symlog", "logit", etc. For alist of available scales, callmatplotlib.scale.get_scale_names().In that case, a suitableNormalize subclass is dynamically generatedand instantiated.

This parameter is ignored ifcolors is set.

vmin, vmaxfloat, optional

When using scalar data and no explicitnorm,vmin andvmax definethe data range that the colormap covers. By default, the colormap coversthe complete value range of the supplied data. It is an error to usevmin/vmax when anorm instance is given (but using astrnormname together withvmin/vmax is acceptable).

Ifvmin orvmax are not given, the default color scaling is based onlevels.

This parameter is ignored ifcolors is set.

origin{None, 'upper', 'lower', 'image'}, default: None

Determines the orientation and exact position ofz by specifying theposition ofz[0,0]. This is only relevant, ifX,Y are not given.

None:z[0,0] is at X=0, Y=0 in the lower left corner.
'lower':z[0,0] is at X=0.5, Y=0.5 in the lower left corner.
'upper':z[0,0] is at X=N+0.5, Y=0.5 in the upper left corner.
'image': Use the value fromrcParams["image.origin"] (default:'upper').

extent(x0, x1, y0, y1), optional

Iforigin is notNone, thenextent is interpreted as inimshow: itgives the outer pixel boundaries. In this case, the position of z[0, 0] isthe center of the pixel, not a corner. Iforigin isNone, then(x0,y0) is the position of z[0, 0], and (x1,y1) is the positionof z[-1, -1].

This argument is ignored ifX andY are specified in the call tocontour.

locatorticker.Locator subclass, optional

The locator is used to determine the contour levels if they are not givenexplicitly vialevels.Defaults toMaxNLocator.

extend{'neither', 'both', 'min', 'max'}, default: 'neither'

Determines thetricontourf-coloring of values that are outside thelevels range.

If 'neither', values outside thelevels range are not colored. If 'min','max' or 'both', color the values below, above or below and above thelevels range.

Values belowmin(levels) and abovemax(levels) are mapped to theunder/over values of theColormap. Note that most colormaps do not havededicated colors for these by default, so that the over and under valuesare the edge values of the colormap. You may want to set these valuesexplicitly usingColormap.set_under andColormap.set_over.

Note

An existingTriContourSet does not get notified if properties of itscolormap are changed. Therefore, an explicit call toContourSet.changed() is needed after modifying the colormap. Theexplicit call can be left out, if a colorbar is assigned to theTriContourSet because it internally callsContourSet.changed().

xunits, yunitsregistered units, optional

Override axis units by specifying an instance of amatplotlib.units.ConversionInterface.

antialiasedbool, optional

Enable antialiasing, overriding the defaults. Forfilled contours, the default isTrue. For line contours,it is taken fromrcParams["lines.antialiased"] (default:True).

hatcheslist[str], optional