Version 3.1.1
matplotlib
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matplotlib.legend_handler

This module defines default legend handlers.

It is strongly encouraged to have read the legend guide before this documentation.

Legend handlers are expected to be a callable object with a following signature.

legend_handler(legend, orig_handle, fontsize, handlebox)

Where legend is the legend itself, orig_handle is the original plot, fontsize is the fontsize in pixels, and handlebox is a OffsetBox instance. Within the call, you should create relevant artists (using relevant properties from the legend and/or orig_handle) and add them into the handlebox. The artists needs to be scaled according to the fontsize (note that the size is in pixel, i.e., this is dpi-scaled value).

This module includes definition of several legend handler classes derived from the base class (HandlerBase) with the following method:

def legend_artist(self, legend, orig_handle, fontsize, handlebox)
class matplotlib.legend_handler.HandlerBase(xpad=0.0, ypad=0.0, update_func=None)[source]

A Base class for default legend handlers.

The derived classes are meant to override create_artists method, which has a following signature.:

def create_artists(self, legend, orig_handle,
                   xdescent, ydescent, width, height, fontsize,
                   trans):

The overridden method needs to create artists of the given transform that fits in the given dimension (xdescent, ydescent, width, height) that are scaled by fontsize if necessary.

adjust_drawing_area(self, legend, orig_handle, xdescent, ydescent, width, height, fontsize)[source]
create_artists(self, legend, orig_handle, xdescent, ydescent, width, height, fontsize, trans)[source]
legend_artist(self, legend, orig_handle, fontsize, handlebox)[source]

Return the artist that this HandlerBase generates for the given original artist/handle.

Parameters:
legend : matplotlib.legend.Legend instance

The legend for which these legend artists are being created.

orig_handle : matplotlib.artist.Artist or similar

The object for which these legend artists are being created.

fontsize : float or int

The fontsize in pixels. The artists being created should be scaled according to the given fontsize.

handlebox : matplotlib.offsetbox.OffsetBox instance

The box which has been created to hold this legend entry's artists. Artists created in the legend_artist method must be added to this handlebox inside this method.

update_prop(self, legend_handle, orig_handle, legend)[source]
class matplotlib.legend_handler.HandlerCircleCollection(yoffsets=None, sizes=None, **kw)[source]

Handler for CircleCollections.

create_collection(self, orig_handle, sizes, offsets, transOffset)[source]
class matplotlib.legend_handler.HandlerErrorbar(xerr_size=0.5, yerr_size=None, marker_pad=0.3, numpoints=None, **kw)[source]

Handler for Errorbars.

create_artists(self, legend, orig_handle, xdescent, ydescent, width, height, fontsize, trans)[source]
get_err_size(self, legend, xdescent, ydescent, width, height, fontsize)[source]
class matplotlib.legend_handler.HandlerLine2D(marker_pad=0.3, numpoints=None, **kw)[source]

Handler for Line2D instances.

Parameters:
marker_pad : float

Padding between points in legend entry.

numpoints : int

Number of points to show in legend entry.

Notes

Any other keyword arguments are given to HandlerNpoints.

create_artists(self, legend, orig_handle, xdescent, ydescent, width, height, fontsize, trans)[source]
class matplotlib.legend_handler.HandlerLineCollection(marker_pad=0.3, numpoints=None, **kw)[source]

Handler for LineCollection instances.

Parameters:
marker_pad : float

Padding between points in legend entry.

numpoints : int

Number of points to show in legend entry.

Notes

Any other keyword arguments are given to HandlerNpoints.

create_artists(self, legend, orig_handle, xdescent, ydescent, width, height, fontsize, trans)[source]
get_numpoints(self, legend)[source]
class matplotlib.legend_handler.HandlerNpoints(marker_pad=0.3, numpoints=None, **kw)[source]

A legend handler that shows numpoints points in the legend entry.

Parameters:
marker_pad : float

Padding between points in legend entry.

numpoints : int

Number of points to show in legend entry.

Notes

Any other keyword arguments are given to HandlerBase.

get_numpoints(self, legend)[source]
get_xdata(self, legend, xdescent, ydescent, width, height, fontsize)[source]
class matplotlib.legend_handler.HandlerNpointsYoffsets(numpoints=None, yoffsets=None, **kw)[source]

A legend handler that shows numpoints in the legend, and allows them to be individually offest in the y-direction.

Parameters:
numpoints : int

Number of points to show in legend entry.

yoffsets : array of floats

Length numpoints list of y offsets for each point in legend entry.

Notes

Any other keyword arguments are given to HandlerNpoints.

get_ydata(self, legend, xdescent, ydescent, width, height, fontsize)[source]
class matplotlib.legend_handler.HandlerPatch(patch_func=None, **kw)[source]

Handler for Patch instances.

Parameters:
patch_func : callable, optional

The function that creates the legend key artist. patch_func should have the signature:

def patch_func(legend=legend, orig_handle=orig_handle,
               xdescent=xdescent, ydescent=ydescent,
               width=width, height=height, fontsize=fontsize)

Subsequently the created artist will have its update_prop method called and the appropriate transform will be applied.

Notes

Any other keyword arguments are given to HandlerBase.

create_artists(self, legend, orig_handle, xdescent, ydescent, width, height, fontsize, trans)[source]
class matplotlib.legend_handler.HandlerPathCollection(yoffsets=None, sizes=None, **kw)[source]

Handler for PathCollections, which are used by scatter.

create_collection(self, orig_handle, sizes, offsets, transOffset)[source]
class matplotlib.legend_handler.HandlerPolyCollection(xpad=0.0, ypad=0.0, update_func=None)[source]

Handler for PolyCollection used in fill_between and stackplot.

create_artists(self, legend, orig_handle, xdescent, ydescent, width, height, fontsize, trans)[source]
class matplotlib.legend_handler.HandlerRegularPolyCollection(yoffsets=None, sizes=None, **kw)[source]

Handler for RegularPolyCollections.

create_artists(self, legend, orig_handle, xdescent, ydescent, width, height, fontsize, trans)[source]
create_collection(self, orig_handle, sizes, offsets, transOffset)[source]
get_numpoints(self, legend)[source]
get_sizes(self, legend, orig_handle, xdescent, ydescent, width, height, fontsize)[source]
update_prop(self, legend_handle, orig_handle, legend)[source]
class matplotlib.legend_handler.HandlerStem(marker_pad=0.3, numpoints=None, bottom=None, yoffsets=None, **kw)[source]

Handler for plots produced by stem.

Parameters:
marker_pad : float

Padding between points in legend entry. Default is 0.3.

numpoints : int, optional

Number of points to show in legend entry.

bottom : float, optional
yoffsets : array of floats, optional

Length numpoints list of y offsets for each point in legend entry.

Notes

Any other keyword arguments are given to HandlerNpointsYoffsets.

create_artists(self, legend, orig_handle, xdescent, ydescent, width, height, fontsize, trans)[source]
get_ydata(self, legend, xdescent, ydescent, width, height, fontsize)[source]
class matplotlib.legend_handler.HandlerTuple(ndivide=1, pad=None, **kwargs)[source]

Handler for Tuple.

Additional kwargs are passed through to HandlerBase.

Parameters:
ndivide : int, optional

The number of sections to divide the legend area into. If None, use the length of the input tuple. Default is 1.

pad : float, optional

If None, fall back to legend.borderpad as the default. In units of fraction of font size. Default is None.

create_artists(self, legend, orig_handle, xdescent, ydescent, width, height, fontsize, trans)[source]
matplotlib.legend_handler.update_from_first_child(tgt, src)[source]