""" Classes for the efficient drawing of large collections of objects that share most properties, e.g., a large number of line segments or polygons. The classes are not meant to be as flexible as their single element counterparts (e.g., you may not be able to select all line styles) but they are meant to be fast for common use cases (e.g., a large set of solid line segments). """ import math from numbers import Number import numpy as np import matplotlib as mpl from . import (_path, artist, cbook, cm, colors as mcolors, docstring, lines as mlines, path as mpath, transforms) import warnings @cbook._define_aliases({ "antialiased": ["antialiaseds", "aa"], "edgecolor": ["edgecolors", "ec"], "facecolor": ["facecolors", "fc"], "linestyle": ["linestyles", "dashes", "ls"], "linewidth": ["linewidths", "lw"], }) class Collection(artist.Artist, cm.ScalarMappable): """ Base class for Collections. Must be subclassed to be usable. All properties in a collection must be sequences or scalars; if scalars, they will be converted to sequences. The property of the ith element of the collection is:: prop[i % len(props)] Exceptions are *capstyle* and *joinstyle* properties, these can only be set globally for the whole collection. Keyword arguments and default values: * *edgecolors*: None * *facecolors*: None * *linewidths*: None * *capstyle*: None * *joinstyle*: None * *antialiaseds*: None * *offsets*: None * *transOffset*: transforms.IdentityTransform() * *offset_position*: 'screen' (default) or 'data' * *norm*: None (optional for :class:`matplotlib.cm.ScalarMappable`) * *cmap*: None (optional for :class:`matplotlib.cm.ScalarMappable`) * *hatch*: None * *zorder*: 1 *offsets* and *transOffset* are used to translate the patch after rendering (default no offsets). If offset_position is 'screen' (default) the offset is applied after the master transform has been applied, that is, the offsets are in screen coordinates. If offset_position is 'data', the offset is applied before the master transform, i.e., the offsets are in data coordinates. If any of *edgecolors*, *facecolors*, *linewidths*, *antialiaseds* are None, they default to their :data:`matplotlib.rcParams` patch setting, in sequence form. The use of :class:`~matplotlib.cm.ScalarMappable` is optional. If the :class:`~matplotlib.cm.ScalarMappable` matrix _A is not None (i.e., a call to set_array has been made), at draw time a call to scalar mappable will be made to set the face colors. """ _offsets = np.zeros((0, 2)) _transOffset = transforms.IdentityTransform() #: Either a list of 3x3 arrays or an Nx3x3 array of transforms, suitable #: for the `all_transforms` argument to #: :meth:`~matplotlib.backend_bases.RendererBase.draw_path_collection`; #: each 3x3 array is used to initialize an #: :class:`~matplotlib.transforms.Affine2D` object. #: Each kind of collection defines this based on its arguments. _transforms = np.empty((0, 3, 3)) # Whether to draw an edge by default. Set on a # subclass-by-subclass basis. _edge_default = False def __init__(self, edgecolors=None, facecolors=None, linewidths=None, linestyles='solid', capstyle=None, joinstyle=None, antialiaseds=None, offsets=None, transOffset=None, norm=None, # optional for ScalarMappable cmap=None, # ditto pickradius=5.0, hatch=None, urls=None, offset_position='screen', zorder=1, **kwargs ): """ Create a Collection %(Collection)s """ artist.Artist.__init__(self) cm.ScalarMappable.__init__(self, norm, cmap) # list of un-scaled dash patterns # this is needed scaling the dash pattern by linewidth self._us_linestyles = [(None, None)] # list of dash patterns self._linestyles = [(None, None)] # list of unbroadcast/scaled linewidths self._us_lw = [0] self._linewidths = [0] self._is_filled = True # May be modified by set_facecolor(). self._hatch_color = mcolors.to_rgba(mpl.rcParams['hatch.color']) self.set_facecolor(facecolors) self.set_edgecolor(edgecolors) self.set_linewidth(linewidths) self.set_linestyle(linestyles) self.set_antialiased(antialiaseds) self.set_pickradius(pickradius) self.set_urls(urls) self.set_hatch(hatch) self.set_offset_position(offset_position) self.set_zorder(zorder) if capstyle: self.set_capstyle(capstyle) else: self._capstyle = None if joinstyle: self.set_joinstyle(joinstyle) else: self._joinstyle = None self._offsets = np.zeros((1, 2)) self._uniform_offsets = None if offsets is not None: offsets = np.asanyarray(offsets, float) # Broadcast (2,) -> (1, 2) but nothing else. if offsets.shape == (2,): offsets = offsets[None, :] if transOffset is not None: self._offsets = offsets self._transOffset = transOffset else: self._uniform_offsets = offsets self._path_effects = None self.update(kwargs) self._paths = None def get_paths(self): return self._paths def set_paths(self): raise NotImplementedError def get_transforms(self): return self._transforms def get_offset_transform(self): t = self._transOffset if (not isinstance(t, transforms.Transform) and hasattr(t, '_as_mpl_transform')): t = t._as_mpl_transform(self.axes) return t def get_datalim(self, transData): transform = self.get_transform() transOffset = self.get_offset_transform() offsets = self._offsets paths = self.get_paths() if not transform.is_affine: paths = [transform.transform_path_non_affine(p) for p in paths] transform = transform.get_affine() if not transOffset.is_affine: offsets = transOffset.transform_non_affine(offsets) transOffset = transOffset.get_affine() if isinstance(offsets, np.ma.MaskedArray): offsets = offsets.filled(np.nan) # get_path_collection_extents handles nan but not masked arrays if len(paths) and len(offsets): result = mpath.get_path_collection_extents( transform.frozen(), paths, self.get_transforms(), offsets, transOffset.frozen()) result = result.inverse_transformed(transData) else: result = transforms.Bbox.null() return result def get_window_extent(self, renderer): # TODO: check to ensure that this does not fail for # cases other than scatter plot legend return self.get_datalim(transforms.IdentityTransform()) def _prepare_points(self): # Helper for drawing and hit testing. transform = self.get_transform() transOffset = self.get_offset_transform() offsets = self._offsets paths = self.get_paths() if self.have_units(): paths = [] for path in self.get_paths(): vertices = path.vertices xs, ys = vertices[:, 0], vertices[:, 1] xs = self.convert_xunits(xs) ys = self.convert_yunits(ys) paths.append(mpath.Path(np.column_stack([xs, ys]), path.codes)) if offsets.size: xs = self.convert_xunits(offsets[:, 0]) ys = self.convert_yunits(offsets[:, 1]) offsets = np.column_stack([xs, ys]) if not transform.is_affine: paths = [transform.transform_path_non_affine(path) for path in paths] transform = transform.get_affine() if not transOffset.is_affine: offsets = transOffset.transform_non_affine(offsets) # This might have changed an ndarray into a masked array. transOffset = transOffset.get_affine() if isinstance(offsets, np.ma.MaskedArray): offsets = offsets.filled(np.nan) # Changing from a masked array to nan-filled ndarray # is probably most efficient at this point. return transform, transOffset, offsets, paths @artist.allow_rasterization def draw(self, renderer): if not self.get_visible(): return renderer.open_group(self.__class__.__name__, self.get_gid()) self.update_scalarmappable() transform, transOffset, offsets, paths = self._prepare_points() gc = renderer.new_gc() self._set_gc_clip(gc) gc.set_snap(self.get_snap()) if self._hatch: gc.set_hatch(self._hatch) try: gc.set_hatch_color(self._hatch_color) except AttributeError: # if we end up with a GC that does not have this method cbook.warn_deprecated( "3.1", message="Your backend does not support setting the " "hatch color; such backends will become unsupported in " "Matplotlib 3.3.") if self.get_sketch_params() is not None: gc.set_sketch_params(*self.get_sketch_params()) if self.get_path_effects(): from matplotlib.patheffects import PathEffectRenderer renderer = PathEffectRenderer(self.get_path_effects(), renderer) # If the collection is made up of a single shape/color/stroke, # it can be rendered once and blitted multiple times, using # `draw_markers` rather than `draw_path_collection`. This is # *much* faster for Agg, and results in smaller file sizes in # PDF/SVG/PS. trans = self.get_transforms() facecolors = self.get_facecolor() edgecolors = self.get_edgecolor() do_single_path_optimization = False if (len(paths) == 1 and len(trans) <= 1 and len(facecolors) == 1 and len(edgecolors) == 1 and len(self._linewidths) == 1 and self._linestyles == [(None, None)] and len(self._antialiaseds) == 1 and len(self._urls) == 1 and self.get_hatch() is None): if len(trans): combined_transform = (transforms.Affine2D(trans[0]) + transform) else: combined_transform = transform extents = paths[0].get_extents(combined_transform) width, height = renderer.get_canvas_width_height() if extents.width < width and extents.height < height: do_single_path_optimization = True if self._joinstyle: gc.set_joinstyle(self._joinstyle) if self._capstyle: gc.set_capstyle(self._capstyle) if do_single_path_optimization: gc.set_foreground(tuple(edgecolors[0])) gc.set_linewidth(self._linewidths[0]) gc.set_dashes(*self._linestyles[0]) gc.set_antialiased(self._antialiaseds[0]) gc.set_url(self._urls[0]) renderer.draw_markers( gc, paths[0], combined_transform.frozen(), mpath.Path(offsets), transOffset, tuple(facecolors[0])) else: renderer.draw_path_collection( gc, transform.frozen(), paths, self.get_transforms(), offsets, transOffset, self.get_facecolor(), self.get_edgecolor(), self._linewidths, self._linestyles, self._antialiaseds, self._urls, self._offset_position) gc.restore() renderer.close_group(self.__class__.__name__) self.stale = False def set_pickradius(self, pr): """ Set the pick radius used for containment tests. Parameters ---------- d : float Pick radius, in points. """ self._pickradius = pr def get_pickradius(self): return self._pickradius def contains(self, mouseevent): """ Test whether the mouse event occurred in the collection. Returns ``bool, dict(ind=itemlist)``, where every item in itemlist contains the event. """ if self._contains is not None: return self._contains(self, mouseevent) if not self.get_visible(): return False, {} pickradius = ( float(self._picker) if isinstance(self._picker, Number) and self._picker is not True # the bool, not just nonzero or 1 else self._pickradius) transform, transOffset, offsets, paths = self._prepare_points() ind = _path.point_in_path_collection( mouseevent.x, mouseevent.y, pickradius, transform.frozen(), paths, self.get_transforms(), offsets, transOffset, pickradius <= 0, self.get_offset_position()) return len(ind) > 0, dict(ind=ind) def set_urls(self, urls): """ Parameters ---------- urls : List[str] or None """ self._urls = urls if urls is not None else [None] self.stale = True def get_urls(self): return self._urls def set_hatch(self, hatch): r""" Set the hatching pattern *hatch* can be one of:: / - diagonal hatching \ - back diagonal | - vertical - - horizontal + - crossed x - crossed diagonal o - small circle O - large circle . - dots * - stars Letters can be combined, in which case all the specified hatchings are done. If same letter repeats, it increases the density of hatching of that pattern. Hatching is supported in the PostScript, PDF, SVG and Agg backends only. Unlike other properties such as linewidth and colors, hatching can only be specified for the collection as a whole, not separately for each member. Parameters ---------- hatch : {'/', '\\', '|', '-', '+', 'x', 'o', 'O', '.', '*'} """ self._hatch = hatch self.stale = True def get_hatch(self): """Return the current hatching pattern.""" return self._hatch def set_offsets(self, offsets): """ Set the offsets for the collection. Parameters ---------- offsets : float or sequence of floats """ offsets = np.asanyarray(offsets, float) if offsets.shape == (2,): # Broadcast (2,) -> (1, 2) but nothing else. offsets = offsets[None, :] # This decision is based on how they are initialized above in __init__. if self._uniform_offsets is None: self._offsets = offsets else: self._uniform_offsets = offsets self.stale = True def get_offsets(self): """Return the offsets for the collection.""" # This decision is based on how they are initialized above in __init__. if self._uniform_offsets is None: return self._offsets else: return self._uniform_offsets def set_offset_position(self, offset_position): """ Set how offsets are applied. If *offset_position* is 'screen' (default) the offset is applied after the master transform has been applied, that is, the offsets are in screen coordinates. If offset_position is 'data', the offset is applied before the master transform, i.e., the offsets are in data coordinates. Parameters ---------- offset_position : {'screen', 'data'} """ cbook._check_in_list(['screen', 'data'], offset_position=offset_position) self._offset_position = offset_position self.stale = True def get_offset_position(self): """ Returns how offsets are applied for the collection. If *offset_position* is 'screen', the offset is applied after the master transform has been applied, that is, the offsets are in screen coordinates. If offset_position is 'data', the offset is applied before the master transform, i.e., the offsets are in data coordinates. """ return self._offset_position def set_linewidth(self, lw): """ Set the linewidth(s) for the collection. *lw* can be a scalar or a sequence; if it is a sequence the patches will cycle through the sequence Parameters ---------- lw : float or sequence of floats """ if lw is None: lw = mpl.rcParams['patch.linewidth'] if lw is None: lw = mpl.rcParams['lines.linewidth'] # get the un-scaled/broadcast lw self._us_lw = np.atleast_1d(np.asarray(lw)) # scale all of the dash patterns. self._linewidths, self._linestyles = self._bcast_lwls( self._us_lw, self._us_linestyles) self.stale = True def set_linestyle(self, ls): """ Set the linestyle(s) for the collection. =========================== ================= linestyle description =========================== ================= ``'-'`` or ``'solid'`` solid line ``'--'`` or ``'dashed'`` dashed line ``'-.'`` or ``'dashdot'`` dash-dotted line ``':'`` or ``'dotted'`` dotted line =========================== ================= Alternatively a dash tuple of the following form can be provided:: (offset, onoffseq), where ``onoffseq`` is an even length tuple of on and off ink in points. Parameters ---------- ls : {'-', '--', '-.', ':', '', (offset, on-off-seq), ...} The line style. """ try: if isinstance(ls, str): ls = cbook.ls_mapper.get(ls, ls) dashes = [mlines._get_dash_pattern(ls)] else: try: dashes = [mlines._get_dash_pattern(ls)] except ValueError: dashes = [mlines._get_dash_pattern(x) for x in ls] except ValueError: raise ValueError( 'Do not know how to convert {!r} to dashes'.format(ls)) # get the list of raw 'unscaled' dash patterns self._us_linestyles = dashes # broadcast and scale the lw and dash patterns self._linewidths, self._linestyles = self._bcast_lwls( self._us_lw, self._us_linestyles) def set_capstyle(self, cs): """ Set the capstyle for the collection (for all its elements). Parameters ---------- cs : {'butt', 'round', 'projecting'} The capstyle """ if cs in ('butt', 'round', 'projecting'): self._capstyle = cs else: raise ValueError('Unrecognized cap style. Found %s' % cs) def get_capstyle(self): return self._capstyle def set_joinstyle(self, js): """ Set the joinstyle for the collection (for all its elements). Parameters ---------- js : {'miter', 'round', 'bevel'} The joinstyle """ if js in ('miter', 'round', 'bevel'): self._joinstyle = js else: raise ValueError('Unrecognized join style. Found %s' % js) def get_joinstyle(self): return self._joinstyle @staticmethod def _bcast_lwls(linewidths, dashes): """ Internal helper function to broadcast + scale ls/lw In the collection drawing code, the linewidth and linestyle are cycled through as circular buffers (via ``v[i % len(v)]``). Thus, if we are going to scale the dash pattern at set time (not draw time) we need to do the broadcasting now and expand both lists to be the same length. Parameters ---------- linewidths : list line widths of collection dashes : list dash specification (offset, (dash pattern tuple)) Returns ------- linewidths, dashes : list Will be the same length, dashes are scaled by paired linewidth """ if mpl.rcParams['_internal.classic_mode']: return linewidths, dashes # make sure they are the same length so we can zip them if len(dashes) != len(linewidths): l_dashes = len(dashes) l_lw = len(linewidths) gcd = math.gcd(l_dashes, l_lw) dashes = list(dashes) * (l_lw // gcd) linewidths = list(linewidths) * (l_dashes // gcd) # scale the dash patters dashes = [mlines._scale_dashes(o, d, lw) for (o, d), lw in zip(dashes, linewidths)] return linewidths, dashes def set_antialiased(self, aa): """ Set the antialiasing state for rendering. Parameters ---------- aa : bool or sequence of bools """ if aa is None: aa = mpl.rcParams['patch.antialiased'] self._antialiaseds = np.atleast_1d(np.asarray(aa, bool)) self.stale = True def set_color(self, c): """ Set both the edgecolor and the facecolor. Parameters ---------- c : color or sequence of rgba tuples See Also -------- Collection.set_facecolor, Collection.set_edgecolor For setting the edge or face color individually. """ self.set_facecolor(c) self.set_edgecolor(c) def _set_facecolor(self, c): if c is None: c = mpl.rcParams['patch.facecolor'] self._is_filled = True try: if c.lower() == 'none': self._is_filled = False except AttributeError: pass self._facecolors = mcolors.to_rgba_array(c, self._alpha) self.stale = True def set_facecolor(self, c): """ Set the facecolor(s) of the collection. *c* can be a matplotlib color spec (all patches have same color), or a sequence of specs; if it is a sequence the patches will cycle through the sequence. If *c* is 'none', the patch will not be filled. Parameters ---------- c : color or sequence of colors """ self._original_facecolor = c self._set_facecolor(c) def get_facecolor(self): return self._facecolors def get_edgecolor(self): if cbook._str_equal(self._edgecolors, 'face'): return self.get_facecolor() else: return self._edgecolors def _set_edgecolor(self, c): set_hatch_color = True if c is None: if (mpl.rcParams['patch.force_edgecolor'] or not self._is_filled or self._edge_default): c = mpl.rcParams['patch.edgecolor'] else: c = 'none' set_hatch_color = False self._is_stroked = True try: if c.lower() == 'none': self._is_stroked = False except AttributeError: pass try: if c.lower() == 'face': # Special case: lookup in "get" method. self._edgecolors = 'face' return except AttributeError: pass self._edgecolors = mcolors.to_rgba_array(c, self._alpha) if set_hatch_color and len(self._edgecolors): self._hatch_color = tuple(self._edgecolors[0]) self.stale = True def set_edgecolor(self, c): """ Set the edgecolor(s) of the collection. Parameters ---------- c : color or sequence of colors or 'face' The collection edgecolor(s). If a sequence, the patches cycle through it. If 'face', match the facecolor. """ self._original_edgecolor = c self._set_edgecolor(c) def set_alpha(self, alpha): """ Set the alpha transparencies of the collection. Parameters ---------- alpha : float or None """ if alpha is not None: try: float(alpha) except TypeError: raise TypeError('alpha must be a float or None') self.update_dict['array'] = True artist.Artist.set_alpha(self, alpha) self._set_facecolor(self._original_facecolor) self._set_edgecolor(self._original_edgecolor) def get_linewidth(self): return self._linewidths def get_linestyle(self): return self._linestyles def update_scalarmappable(self): """Update colors from the scalar mappable array, if it is not None.""" if self._A is None: return if self._A.ndim > 1: raise ValueError('Collections can only map rank 1 arrays') if not self.check_update("array"): return if self._is_filled: self._facecolors = self.to_rgba(self._A, self._alpha) elif self._is_stroked: self._edgecolors = self.to_rgba(self._A, self._alpha) self.stale = True def get_fill(self): 'return whether fill is set' return self._is_filled def update_from(self, other): 'copy properties from other to self' artist.Artist.update_from(self, other) self._antialiaseds = other._antialiaseds self._original_edgecolor = other._original_edgecolor self._edgecolors = other._edgecolors self._original_facecolor = other._original_facecolor self._facecolors = other._facecolors self._linewidths = other._linewidths self._linestyles = other._linestyles self._us_linestyles = other._us_linestyles self._pickradius = other._pickradius self._hatch = other._hatch # update_from for scalarmappable self._A = other._A self.norm = other.norm self.cmap = other.cmap # self.update_dict = other.update_dict # do we need to copy this? -JJL self.stale = True # these are not available for the object inspector until after the # class is built so we define an initial set here for the init # function and they will be overridden after object defn docstring.interpd.update(Collection="""\ Valid Collection keyword arguments: * *edgecolors*: None * *facecolors*: None * *linewidths*: None * *antialiaseds*: None * *offsets*: None * *transOffset*: transforms.IdentityTransform() * *norm*: None (optional for :class:`matplotlib.cm.ScalarMappable`) * *cmap*: None (optional for :class:`matplotlib.cm.ScalarMappable`) *offsets* and *transOffset* are used to translate the patch after rendering (default no offsets) If any of *edgecolors*, *facecolors*, *linewidths*, *antialiaseds* are None, they default to their :data:`matplotlib.rcParams` patch setting, in sequence form. """) class _CollectionWithSizes(Collection): """ Base class for collections that have an array of sizes. """ _factor = 1.0 def get_sizes(self): """ Returns the sizes of the elements in the collection. The value represents the 'area' of the element. Returns ------- sizes : array The 'area' of each element. """ return self._sizes def set_sizes(self, sizes, dpi=72.0): """ Set the sizes of each member of the collection. Parameters ---------- sizes : ndarray or None The size to set for each element of the collection. The value is the 'area' of the element. dpi : float The dpi of the canvas. Defaults to 72.0. """ if sizes is None: self._sizes = np.array([]) self._transforms = np.empty((0, 3, 3)) else: self._sizes = np.asarray(sizes) self._transforms = np.zeros((len(self._sizes), 3, 3)) scale = np.sqrt(self._sizes) * dpi / 72.0 * self._factor self._transforms[:, 0, 0] = scale self._transforms[:, 1, 1] = scale self._transforms[:, 2, 2] = 1.0 self.stale = True @artist.allow_rasterization def draw(self, renderer): self.set_sizes(self._sizes, self.figure.dpi) Collection.draw(self, renderer) class PathCollection(_CollectionWithSizes): """ This is the most basic :class:`Collection` subclass. A :class:`PathCollection` is e.g. created by a :meth:`~.Axes.scatter` plot. """ @docstring.dedent_interpd def __init__(self, paths, sizes=None, **kwargs): """ *paths* is a sequence of :class:`matplotlib.path.Path` instances. %(Collection)s """ Collection.__init__(self, **kwargs) self.set_paths(paths) self.set_sizes(sizes) self.stale = True def set_paths(self, paths): self._paths = paths self.stale = True def get_paths(self): return self._paths def legend_elements(self, prop="colors", num="auto", fmt=None, func=lambda x: x, **kwargs): """ Creates legend handles and labels for a PathCollection. This is useful for obtaining a legend for a :meth:`~.Axes.scatter` plot. E.g.:: scatter = plt.scatter([1,2,3], [4,5,6], c=[7,2,3]) plt.legend(*scatter.legend_elements()) Also see the :ref:`automatedlegendcreation` example. Parameters ---------- prop : string, optional, default *"colors"* Can be *"colors"* or *"sizes"*. In case of *"colors"*, the legend handles will show the different colors of the collection. In case of "sizes", the legend will show the different sizes. num : int, None, "auto" (default), array-like, or `~.ticker.Locator`, optional Target number of elements to create. If None, use all unique elements of the mappable array. If an integer, target to use *num* elements in the normed range. If *"auto"*, try to determine which option better suits the nature of the data. The number of created elements may slightly deviate from *num* due to a `~.ticker.Locator` being used to find useful locations. If a list or array, use exactly those elements for the legend. Finally, a `~.ticker.Locator` can be provided. fmt : string, `~matplotlib.ticker.Formatter`, or None (default) The format or formatter to use for the labels. If a string must be a valid input for a `~.StrMethodFormatter`. If None (the default), use a `~.ScalarFormatter`. func : function, default *lambda x: x* Function to calculate the labels. Often the size (or color) argument to :meth:`~.Axes.scatter` will have been pre-processed by the user using a function *s = f(x)* to make the markers visible; e.g. *size = np.log10(x)*. Providing the inverse of this function here allows that pre-processing to be inverted, so that the legend labels have the correct values; e.g. *func = np.exp(x, 10)*. kwargs : further parameters Allowed kwargs are *color* and *size*. E.g. it may be useful to set the color of the markers if *prop="sizes"* is used; similarly to set the size of the markers if *prop="colors"* is used. Any further parameters are passed onto the `.Line2D` instance. This may be useful to e.g. specify a different *markeredgecolor* or *alpha* for the legend handles. Returns ------- tuple (handles, labels) with *handles* being a list of `.Line2D` objects and *labels* a matching list of strings. """ handles = [] labels = [] hasarray = self.get_array() is not None if fmt is None: fmt = mpl.ticker.ScalarFormatter(useOffset=False, useMathText=True) elif isinstance(fmt, str): fmt = mpl.ticker.StrMethodFormatter(fmt) fmt.create_dummy_axis() if prop == "colors": if not hasarray: warnings.warn("Collection without array used. Make sure to " "specify the values to be colormapped via the " "`c` argument.") return handles, labels u = np.unique(self.get_array()) size = kwargs.pop("size", mpl.rcParams["lines.markersize"]) elif prop == "sizes": u = np.unique(self.get_sizes()) color = kwargs.pop("color", "k") else: raise ValueError("Valid values for `prop` are 'colors' or " f"'sizes'. You supplied '{prop}' instead.") fmt.set_bounds(func(u).min(), func(u).max()) if num == "auto": num = 9 if len(u) <= num: num = None if num is None: values = u label_values = func(values) else: if prop == "colors": arr = self.get_array() elif prop == "sizes": arr = self.get_sizes() if isinstance(num, mpl.ticker.Locator): loc = num elif np.iterable(num): loc = mpl.ticker.FixedLocator(num) else: num = int(num) loc = mpl.ticker.MaxNLocator(nbins=num, min_n_ticks=num-1, steps=[1, 2, 2.5, 3, 5, 6, 8, 10]) label_values = loc.tick_values(func(arr).min(), func(arr).max()) cond = ((label_values >= func(arr).min()) & (label_values <= func(arr).max())) label_values = label_values[cond] xarr = np.linspace(arr.min(), arr.max(), 256) values = np.interp(label_values, func(xarr), xarr) kw = dict(markeredgewidth=self.get_linewidths()[0], alpha=self.get_alpha()) kw.update(kwargs) for val, lab in zip(values, label_values): if prop == "colors": color = self.cmap(self.norm(val)) elif prop == "sizes": size = np.sqrt(val) if np.isclose(size, 0.0): continue h = mlines.Line2D([0], [0], ls="", color=color, ms=size, marker=self.get_paths()[0], **kw) handles.append(h) if hasattr(fmt, "set_locs"): fmt.set_locs(label_values) l = fmt(lab) labels.append(l) return handles, labels class PolyCollection(_CollectionWithSizes): @docstring.dedent_interpd def __init__(self, verts, sizes=None, closed=True, **kwargs): """ *verts* is a sequence of ( *verts0*, *verts1*, ...) where *verts_i* is a sequence of *xy* tuples of vertices, or an equivalent :mod:`numpy` array of shape (*nv*, 2). *sizes* is *None* (default) or a sequence of floats that scale the corresponding *verts_i*. The scaling is applied before the Artist master transform; if the latter is an identity transform, then the overall scaling is such that if *verts_i* specify a unit square, then *sizes_i* is the area of that square in points^2. If len(*sizes*) < *nv*, the additional values will be taken cyclically from the array. *closed*, when *True*, will explicitly close the polygon. %(Collection)s """ Collection.__init__(self, **kwargs) self.set_sizes(sizes) self.set_verts(verts, closed) self.stale = True def set_verts(self, verts, closed=True): '''This allows one to delay initialization of the vertices.''' if isinstance(verts, np.ma.MaskedArray): verts = verts.astype(float).filled(np.nan) # This is much faster than having Path do it one at a time. if closed: self._paths = [] for xy in verts: if len(xy): if isinstance(xy, np.ma.MaskedArray): xy = np.ma.concatenate([xy, xy[0:1]]) else: xy = np.asarray(xy) xy = np.concatenate([xy, xy[0:1]]) codes = np.empty(xy.shape[0], dtype=mpath.Path.code_type) codes[:] = mpath.Path.LINETO codes[0] = mpath.Path.MOVETO codes[-1] = mpath.Path.CLOSEPOLY self._paths.append(mpath.Path(xy, codes)) else: self._paths.append(mpath.Path(xy)) else: self._paths = [mpath.Path(xy) for xy in verts] self.stale = True set_paths = set_verts def set_verts_and_codes(self, verts, codes): """This allows one to initialize vertices with path codes.""" if len(verts) != len(codes): raise ValueError("'codes' must be a 1D list or array " "with the same length of 'verts'") self._paths = [] for xy, cds in zip(verts, codes): if len(xy): self._paths.append(mpath.Path(xy, cds)) else: self._paths.append(mpath.Path(xy)) self.stale = True class BrokenBarHCollection(PolyCollection): """ A collection of horizontal bars spanning *yrange* with a sequence of *xranges*. """ @docstring.dedent_interpd def __init__(self, xranges, yrange, **kwargs): """ *xranges* sequence of (*xmin*, *xwidth*) *yrange* *ymin*, *ywidth* %(Collection)s """ ymin, ywidth = yrange ymax = ymin + ywidth verts = [[(xmin, ymin), (xmin, ymax), (xmin + xwidth, ymax), (xmin + xwidth, ymin), (xmin, ymin)] for xmin, xwidth in xranges] PolyCollection.__init__(self, verts, **kwargs) @staticmethod def span_where(x, ymin, ymax, where, **kwargs): """ Create a BrokenBarHCollection to plot horizontal bars from over the regions in *x* where *where* is True. The bars range on the y-axis from *ymin* to *ymax* A :class:`BrokenBarHCollection` is returned. *kwargs* are passed on to the collection. """ xranges = [] for ind0, ind1 in cbook.contiguous_regions(where): xslice = x[ind0:ind1] if not len(xslice): continue xranges.append((xslice[0], xslice[-1] - xslice[0])) collection = BrokenBarHCollection( xranges, [ymin, ymax - ymin], **kwargs) return collection class RegularPolyCollection(_CollectionWithSizes): """Draw a collection of regular polygons with *numsides*.""" _path_generator = mpath.Path.unit_regular_polygon _factor = np.pi ** (-1/2) @docstring.dedent_interpd def __init__(self, numsides, rotation=0, sizes=(1,), **kwargs): """ *numsides* the number of sides of the polygon *rotation* the rotation of the polygon in radians *sizes* gives the area of the circle circumscribing the regular polygon in points^2 %(Collection)s Example: see :doc:`/gallery/event_handling/lasso_demo` for a complete example:: offsets = np.random.rand(20,2) facecolors = [cm.jet(x) for x in np.random.rand(20)] black = (0,0,0,1) collection = RegularPolyCollection( numsides=5, # a pentagon rotation=0, sizes=(50,), facecolors=facecolors, edgecolors=(black,), linewidths=(1,), offsets=offsets, transOffset=ax.transData, ) """ Collection.__init__(self, **kwargs) self.set_sizes(sizes) self._numsides = numsides self._paths = [self._path_generator(numsides)] self._rotation = rotation self.set_transform(transforms.IdentityTransform()) def get_numsides(self): return self._numsides def get_rotation(self): return self._rotation @artist.allow_rasterization def draw(self, renderer): self.set_sizes(self._sizes, self.figure.dpi) self._transforms = [ transforms.Affine2D(x).rotate(-self._rotation).get_matrix() for x in self._transforms ] Collection.draw(self, renderer) class StarPolygonCollection(RegularPolyCollection): """Draw a collection of regular stars with *numsides* points.""" _path_generator = mpath.Path.unit_regular_star class AsteriskPolygonCollection(RegularPolyCollection): """Draw a collection of regular asterisks with *numsides* points.""" _path_generator = mpath.Path.unit_regular_asterisk class LineCollection(Collection): """ All parameters must be sequences or scalars; if scalars, they will be converted to sequences. The property of the ith line segment is:: prop[i % len(props)] i.e., the properties cycle if the ``len`` of props is less than the number of segments. """ _edge_default = True def __init__(self, segments, # Can be None. linewidths=None, colors=None, antialiaseds=None, linestyles='solid', offsets=None, transOffset=None, norm=None, cmap=None, pickradius=5, zorder=2, facecolors='none', **kwargs ): """ Parameters ---------- segments A sequence of (*line0*, *line1*, *line2*), where:: linen = (x0, y0), (x1, y1), ... (xm, ym) or the equivalent numpy array with two columns. Each line can be a different length. colors : sequence, optional A sequence of RGBA tuples (e.g., arbitrary color strings, etc, not allowed). antialiaseds : sequence, optional A sequence of ones or zeros. linestyles : string, tuple, optional Either one of [ 'solid' | 'dashed' | 'dashdot' | 'dotted' ], or a dash tuple. The dash tuple is:: (offset, onoffseq) where ``onoffseq`` is an even length tuple of on and off ink in points. norm : Normalize, optional `~.colors.Normalize` instance. cmap : string or Colormap, optional Colormap name or `~.colors.Colormap` instance. pickradius : float, optional The tolerance in points for mouse clicks picking a line. Default is 5 pt. zorder : int, optional zorder of the LineCollection. Default is 2. facecolors : optional The facecolors of the LineCollection. Default is 'none'. Setting to a value other than 'none' will lead to a filled polygon being drawn between points on each line. Notes ----- If *linewidths*, *colors*, or *antialiaseds* is None, they default to their rcParams setting, in sequence form. If *offsets* and *transOffset* are not None, then *offsets* are transformed by *transOffset* and applied after the segments have been transformed to display coordinates. If *offsets* is not None but *transOffset* is None, then the *offsets* are added to the segments before any transformation. In this case, a single offset can be specified as:: offsets=(xo,yo) and this value will be added cumulatively to each successive segment, so as to produce a set of successively offset curves. The use of :class:`~matplotlib.cm.ScalarMappable` is optional. If the :class:`~matplotlib.cm.ScalarMappable` array :attr:`~matplotlib.cm.ScalarMappable._A` is not None (i.e., a call to :meth:`~matplotlib.cm.ScalarMappable.set_array` has been made), at draw time a call to scalar mappable will be made to set the colors. """ if colors is None: colors = mpl.rcParams['lines.color'] if linewidths is None: linewidths = (mpl.rcParams['lines.linewidth'],) if antialiaseds is None: antialiaseds = (mpl.rcParams['lines.antialiased'],) colors = mcolors.to_rgba_array(colors) Collection.__init__( self, edgecolors=colors, facecolors=facecolors, linewidths=linewidths, linestyles=linestyles, antialiaseds=antialiaseds, offsets=offsets, transOffset=transOffset, norm=norm, cmap=cmap, pickradius=pickradius, zorder=zorder, **kwargs) self.set_segments(segments) def set_segments(self, segments): if segments is None: return _segments = [] for seg in segments: if not isinstance(seg, np.ma.MaskedArray): seg = np.asarray(seg, float) _segments.append(seg) if self._uniform_offsets is not None: _segments = self._add_offsets(_segments) self._paths = [mpath.Path(_seg) for _seg in _segments] self.stale = True set_verts = set_segments # for compatibility with PolyCollection set_paths = set_segments def get_segments(self): """ Returns ------- segments : list List of segments in the LineCollection. Each list item contains an array of vertices. """ segments = [] for path in self._paths: vertices = [vertex for vertex, _ in path.iter_segments()] vertices = np.asarray(vertices) segments.append(vertices) return segments def _add_offsets(self, segs): offsets = self._uniform_offsets Nsegs = len(segs) Noffs = offsets.shape[0] if Noffs == 1: for i in range(Nsegs): segs[i] = segs[i] + i * offsets else: for i in range(Nsegs): io = i % Noffs segs[i] = segs[i] + offsets[io:io + 1] return segs def set_color(self, c): """ Set the color(s) of the LineCollection. Parameters ---------- c : color or list of colors Matplotlib color argument (all patches have same color), or a sequence or rgba tuples; if it is a sequence the patches will cycle through the sequence. """ self.set_edgecolor(c) self.stale = True def get_color(self): return self._edgecolors get_colors = get_color # for compatibility with old versions class EventCollection(LineCollection): """ A collection of discrete events. The events are given by a 1-dimensional array, usually the position of something along an axis, such as time or length. They do not have an amplitude and are displayed as vertical or horizontal parallel bars. """ _edge_default = True def __init__(self, positions, # Cannot be None. orientation=None, lineoffset=0, linelength=1, linewidth=None, color=None, linestyle='solid', antialiased=None, **kwargs ): """ Parameters ---------- positions : 1D array-like object Each value is an event. orientation : {None, 'horizontal', 'vertical'}, optional The orientation of the **collection** (the event bars are along the orthogonal direction). Defaults to 'horizontal' if not specified or None. lineoffset : scalar, optional, default: 0 The offset of the center of the markers from the origin, in the direction orthogonal to *orientation*. linelength : scalar, optional, default: 1 The total height of the marker (i.e. the marker stretches from ``lineoffset - linelength/2`` to ``lineoffset + linelength/2``). linewidth : scalar or None, optional, default: None If it is None, defaults to its rcParams setting, in sequence form. color : color, sequence of colors or None, optional, default: None If it is None, defaults to its rcParams setting, in sequence form. linestyle : str or tuple, optional, default: 'solid' Valid strings are ['solid', 'dashed', 'dashdot', 'dotted', '-', '--', '-.', ':']. Dash tuples should be of the form:: (offset, onoffseq), where *onoffseq* is an even length tuple of on and off ink in points. antialiased : {None, 1, 2}, optional If it is None, defaults to its rcParams setting, in sequence form. **kwargs : optional Other keyword arguments are line collection properties. See :class:`~matplotlib.collections.LineCollection` for a list of the valid properties. Examples -------- .. plot:: gallery/lines_bars_and_markers/eventcollection_demo.py """ if positions is None: raise ValueError('positions must be an array-like object') # Force a copy of positions positions = np.array(positions, copy=True) segment = (lineoffset + linelength / 2., lineoffset - linelength / 2.) if positions.size == 0: segments = [] elif positions.ndim > 1: raise ValueError('positions cannot be an array with more than ' 'one dimension.') elif (orientation is None or orientation.lower() == 'none' or orientation.lower() == 'horizontal'): positions.sort() segments = [[(coord1, coord2) for coord2 in segment] for coord1 in positions] self._is_horizontal = True elif orientation.lower() == 'vertical': positions.sort() segments = [[(coord2, coord1) for coord2 in segment] for coord1 in positions] self._is_horizontal = False else: cbook._check_in_list(['horizontal', 'vertical'], orientation=orientation) LineCollection.__init__(self, segments, linewidths=linewidth, colors=color, antialiaseds=antialiased, linestyles=linestyle, **kwargs) self._linelength = linelength self._lineoffset = lineoffset def get_positions(self): ''' return an array containing the floating-point values of the positions ''' segments = self.get_segments() pos = 0 if self.is_horizontal() else 1 return [segment[0, pos] for segment in self.get_segments()] def set_positions(self, positions): ''' set the positions of the events to the specified value ''' if positions is None or (hasattr(positions, 'len') and len(positions) == 0): self.set_segments([]) return lineoffset = self.get_lineoffset() linelength = self.get_linelength() segment = (lineoffset + linelength / 2., lineoffset - linelength / 2.) positions = np.asanyarray(positions) positions.sort() if self.is_horizontal(): segments = [[(coord1, coord2) for coord2 in segment] for coord1 in positions] else: segments = [[(coord2, coord1) for coord2 in segment] for coord1 in positions] self.set_segments(segments) def add_positions(self, position): ''' add one or more events at the specified positions ''' if position is None or (hasattr(position, 'len') and len(position) == 0): return positions = self.get_positions() positions = np.hstack([positions, np.asanyarray(position)]) self.set_positions(positions) extend_positions = append_positions = add_positions def is_horizontal(self): ''' True if the eventcollection is horizontal, False if vertical ''' return self._is_horizontal def get_orientation(self): ''' get the orientation of the event line, may be: [ 'horizontal' | 'vertical' ] ''' return 'horizontal' if self.is_horizontal() else 'vertical' def switch_orientation(self): ''' switch the orientation of the event line, either from vertical to horizontal or vice versus ''' segments = self.get_segments() for i, segment in enumerate(segments): segments[i] = np.fliplr(segment) self.set_segments(segments) self._is_horizontal = not self.is_horizontal() self.stale = True def set_orientation(self, orientation=None): ''' set the orientation of the event line [ 'horizontal' | 'vertical' | None ] defaults to 'horizontal' if not specified or None ''' if (orientation is None or orientation.lower() == 'none' or orientation.lower() == 'horizontal'): is_horizontal = True elif orientation.lower() == 'vertical': is_horizontal = False else: cbook._check_in_list(['horizontal', 'vertical'], orientation=orientation) if is_horizontal == self.is_horizontal(): return self.switch_orientation() def get_linelength(self): ''' get the length of the lines used to mark each event ''' return self._linelength def set_linelength(self, linelength): ''' set the length of the lines used to mark each event ''' if linelength == self.get_linelength(): return lineoffset = self.get_lineoffset() segments = self.get_segments() pos = 1 if self.is_horizontal() else 0 for segment in segments: segment[0, pos] = lineoffset + linelength / 2. segment[1, pos] = lineoffset - linelength / 2. self.set_segments(segments) self._linelength = linelength def get_lineoffset(self): ''' get the offset of the lines used to mark each event ''' return self._lineoffset def set_lineoffset(self, lineoffset): ''' set the offset of the lines used to mark each event ''' if lineoffset == self.get_lineoffset(): return linelength = self.get_linelength() segments = self.get_segments() pos = 1 if self.is_horizontal() else 0 for segment in segments: segment[0, pos] = lineoffset + linelength / 2. segment[1, pos] = lineoffset - linelength / 2. self.set_segments(segments) self._lineoffset = lineoffset def get_linewidth(self): """Get the width of the lines used to mark each event.""" return super(EventCollection, self).get_linewidth()[0] def get_linewidths(self): return super(EventCollection, self).get_linewidth() def get_color(self): ''' get the color of the lines used to mark each event ''' return self.get_colors()[0] class CircleCollection(_CollectionWithSizes): """A collection of circles, drawn using splines.""" _factor = np.pi ** (-1/2) @docstring.dedent_interpd def __init__(self, sizes, **kwargs): """ *sizes* Gives the area of the circle in points^2 %(Collection)s """ Collection.__init__(self, **kwargs) self.set_sizes(sizes) self.set_transform(transforms.IdentityTransform()) self._paths = [mpath.Path.unit_circle()] class EllipseCollection(Collection): """A collection of ellipses, drawn using splines.""" @docstring.dedent_interpd def __init__(self, widths, heights, angles, units='points', **kwargs): """ Parameters ---------- widths : array-like The lengths of the first axes (e.g., major axis lengths). heights : array-like The lengths of second axes. angles : array-like The angles of the first axes, degrees CCW from the x-axis. units : {'points', 'inches', 'dots', 'width', 'height', 'x', 'y', 'xy'} The units in which majors and minors are given; 'width' and 'height' refer to the dimensions of the axes, while 'x' and 'y' refer to the *offsets* data units. 'xy' differs from all others in that the angle as plotted varies with the aspect ratio, and equals the specified angle only when the aspect ratio is unity. Hence it behaves the same as the :class:`~matplotlib.patches.Ellipse` with ``axes.transData`` as its transform. Other Parameters ---------------- **kwargs Additional kwargs inherited from the base :class:`Collection`. %(Collection)s """ Collection.__init__(self, **kwargs) self._widths = 0.5 * np.asarray(widths).ravel() self._heights = 0.5 * np.asarray(heights).ravel() self._angles = np.deg2rad(angles).ravel() self._units = units self.set_transform(transforms.IdentityTransform()) self._transforms = np.empty((0, 3, 3)) self._paths = [mpath.Path.unit_circle()] def _set_transforms(self): """Calculate transforms immediately before drawing.""" ax = self.axes fig = self.figure if self._units == 'xy': sc = 1 elif self._units == 'x': sc = ax.bbox.width / ax.viewLim.width elif self._units == 'y': sc = ax.bbox.height / ax.viewLim.height elif self._units == 'inches': sc = fig.dpi elif self._units == 'points': sc = fig.dpi / 72.0 elif self._units == 'width': sc = ax.bbox.width elif self._units == 'height': sc = ax.bbox.height elif self._units == 'dots': sc = 1.0 else: raise ValueError('unrecognized units: %s' % self._units) self._transforms = np.zeros((len(self._widths), 3, 3)) widths = self._widths * sc heights = self._heights * sc sin_angle = np.sin(self._angles) cos_angle = np.cos(self._angles) self._transforms[:, 0, 0] = widths * cos_angle self._transforms[:, 0, 1] = heights * -sin_angle self._transforms[:, 1, 0] = widths * sin_angle self._transforms[:, 1, 1] = heights * cos_angle self._transforms[:, 2, 2] = 1.0 _affine = transforms.Affine2D if self._units == 'xy': m = ax.transData.get_affine().get_matrix().copy() m[:2, 2:] = 0 self.set_transform(_affine(m)) @artist.allow_rasterization def draw(self, renderer): self._set_transforms() Collection.draw(self, renderer) class PatchCollection(Collection): """ A generic collection of patches. This makes it easier to assign a color map to a heterogeneous collection of patches. This also may improve plotting speed, since PatchCollection will draw faster than a large number of patches. """ def __init__(self, patches, match_original=False, **kwargs): """ *patches* a sequence of Patch objects. This list may include a heterogeneous assortment of different patch types. *match_original* If True, use the colors and linewidths of the original patches. If False, new colors may be assigned by providing the standard collection arguments, facecolor, edgecolor, linewidths, norm or cmap. If any of *edgecolors*, *facecolors*, *linewidths*, *antialiaseds* are None, they default to their :data:`matplotlib.rcParams` patch setting, in sequence form. The use of :class:`~matplotlib.cm.ScalarMappable` is optional. If the :class:`~matplotlib.cm.ScalarMappable` matrix _A is not None (i.e., a call to set_array has been made), at draw time a call to scalar mappable will be made to set the face colors. """ if match_original: def determine_facecolor(patch): if patch.get_fill(): return patch.get_facecolor() return [0, 0, 0, 0] kwargs['facecolors'] = [determine_facecolor(p) for p in patches] kwargs['edgecolors'] = [p.get_edgecolor() for p in patches] kwargs['linewidths'] = [p.get_linewidth() for p in patches] kwargs['linestyles'] = [p.get_linestyle() for p in patches] kwargs['antialiaseds'] = [p.get_antialiased() for p in patches] Collection.__init__(self, **kwargs) self.set_paths(patches) def set_paths(self, patches): paths = [p.get_transform().transform_path(p.get_path()) for p in patches] self._paths = paths class TriMesh(Collection): """ Class for the efficient drawing of a triangular mesh using Gouraud shading. A triangular mesh is a `~matplotlib.tri.Triangulation` object. """ def __init__(self, triangulation, **kwargs): Collection.__init__(self, **kwargs) self._triangulation = triangulation self._shading = 'gouraud' self._is_filled = True self._bbox = transforms.Bbox.unit() # Unfortunately this requires a copy, unless Triangulation # was rewritten. xy = np.hstack((triangulation.x.reshape(-1, 1), triangulation.y.reshape(-1, 1))) self._bbox.update_from_data_xy(xy) def get_paths(self): if self._paths is None: self.set_paths() return self._paths def set_paths(self): self._paths = self.convert_mesh_to_paths(self._triangulation) @staticmethod def convert_mesh_to_paths(tri): """ Converts a given mesh into a sequence of `~.Path` objects. This function is primarily of use to implementers of backends that do not directly support meshes. """ triangles = tri.get_masked_triangles() verts = np.stack((tri.x[triangles], tri.y[triangles]), axis=-1) return [mpath.Path(x) for x in verts] @artist.allow_rasterization def draw(self, renderer): if not self.get_visible(): return renderer.open_group(self.__class__.__name__) transform = self.get_transform() # Get a list of triangles and the color at each vertex. tri = self._triangulation triangles = tri.get_masked_triangles() verts = np.stack((tri.x[triangles], tri.y[triangles]), axis=-1) self.update_scalarmappable() colors = self._facecolors[triangles] gc = renderer.new_gc() self._set_gc_clip(gc) gc.set_linewidth(self.get_linewidth()[0]) renderer.draw_gouraud_triangles(gc, verts, colors, transform.frozen()) gc.restore() renderer.close_group(self.__class__.__name__) class QuadMesh(Collection): """ Class for the efficient drawing of a quadrilateral mesh. A quadrilateral mesh consists of a grid of vertices. The dimensions of this array are (*meshWidth* + 1, *meshHeight* + 1). Each vertex in the mesh has a different set of "mesh coordinates" representing its position in the topology of the mesh. For any values (*m*, *n*) such that 0 <= *m* <= *meshWidth* and 0 <= *n* <= *meshHeight*, the vertices at mesh coordinates (*m*, *n*), (*m*, *n* + 1), (*m* + 1, *n* + 1), and (*m* + 1, *n*) form one of the quadrilaterals in the mesh. There are thus (*meshWidth* * *meshHeight*) quadrilaterals in the mesh. The mesh need not be regular and the polygons need not be convex. A quadrilateral mesh is represented by a (2 x ((*meshWidth* + 1) * (*meshHeight* + 1))) numpy array *coordinates*, where each row is the *x* and *y* coordinates of one of the vertices. To define the function that maps from a data point to its corresponding color, use the :meth:`set_cmap` method. Each of these arrays is indexed in row-major order by the mesh coordinates of the vertex (or the mesh coordinates of the lower left vertex, in the case of the colors). For example, the first entry in *coordinates* is the coordinates of the vertex at mesh coordinates (0, 0), then the one at (0, 1), then at (0, 2) .. (0, meshWidth), (1, 0), (1, 1), and so on. *shading* may be 'flat', or 'gouraud' """ def __init__(self, meshWidth, meshHeight, coordinates, antialiased=True, shading='flat', **kwargs): Collection.__init__(self, **kwargs) self._meshWidth = meshWidth self._meshHeight = meshHeight # By converting to floats now, we can avoid that on every draw. self._coordinates = np.asarray(coordinates, float).reshape( (meshHeight + 1, meshWidth + 1, 2)) self._antialiased = antialiased self._shading = shading self._bbox = transforms.Bbox.unit() self._bbox.update_from_data_xy(coordinates.reshape( ((meshWidth + 1) * (meshHeight + 1), 2))) def get_paths(self): if self._paths is None: self.set_paths() return self._paths def set_paths(self): self._paths = self.convert_mesh_to_paths( self._meshWidth, self._meshHeight, self._coordinates) self.stale = True def get_datalim(self, transData): return (self.get_transform() - transData).transform_bbox(self._bbox) @staticmethod def convert_mesh_to_paths(meshWidth, meshHeight, coordinates): """ Converts a given mesh into a sequence of `~.Path` objects. This function is primarily of use to implementers of backends that do not directly support quadmeshes. """ if isinstance(coordinates, np.ma.MaskedArray): c = coordinates.data else: c = coordinates points = np.concatenate(( c[:-1, :-1], c[:-1, 1:], c[1:, 1:], c[1:, :-1], c[:-1, :-1] ), axis=2) points = points.reshape((meshWidth * meshHeight, 5, 2)) return [mpath.Path(x) for x in points] def convert_mesh_to_triangles(self, meshWidth, meshHeight, coordinates): """ Converts a given mesh into a sequence of triangles, each point with its own color. This is useful for experiments using `draw_gouraud_triangle`. """ if isinstance(coordinates, np.ma.MaskedArray): p = coordinates.data else: p = coordinates p_a = p[:-1, :-1] p_b = p[:-1, 1:] p_c = p[1:, 1:] p_d = p[1:, :-1] p_center = (p_a + p_b + p_c + p_d) / 4.0 triangles = np.concatenate(( p_a, p_b, p_center, p_b, p_c, p_center, p_c, p_d, p_center, p_d, p_a, p_center, ), axis=2) triangles = triangles.reshape((meshWidth * meshHeight * 4, 3, 2)) c = self.get_facecolor().reshape((meshHeight + 1, meshWidth + 1, 4)) c_a = c[:-1, :-1] c_b = c[:-1, 1:] c_c = c[1:, 1:] c_d = c[1:, :-1] c_center = (c_a + c_b + c_c + c_d) / 4.0 colors = np.concatenate(( c_a, c_b, c_center, c_b, c_c, c_center, c_c, c_d, c_center, c_d, c_a, c_center, ), axis=2) colors = colors.reshape((meshWidth * meshHeight * 4, 3, 4)) return triangles, colors @artist.allow_rasterization def draw(self, renderer): if not self.get_visible(): return renderer.open_group(self.__class__.__name__, self.get_gid()) transform = self.get_transform() transOffset = self.get_offset_transform() offsets = self._offsets if self.have_units(): if len(self._offsets): xs = self.convert_xunits(self._offsets[:, 0]) ys = self.convert_yunits(self._offsets[:, 1]) offsets = np.column_stack([xs, ys]) self.update_scalarmappable() if not transform.is_affine: coordinates = self._coordinates.reshape((-1, 2)) coordinates = transform.transform(coordinates) coordinates = coordinates.reshape(self._coordinates.shape) transform = transforms.IdentityTransform() else: coordinates = self._coordinates if not transOffset.is_affine: offsets = transOffset.transform_non_affine(offsets) transOffset = transOffset.get_affine() gc = renderer.new_gc() self._set_gc_clip(gc) gc.set_linewidth(self.get_linewidth()[0]) if self._shading == 'gouraud': triangles, colors = self.convert_mesh_to_triangles( self._meshWidth, self._meshHeight, coordinates) renderer.draw_gouraud_triangles( gc, triangles, colors, transform.frozen()) else: renderer.draw_quad_mesh( gc, transform.frozen(), self._meshWidth, self._meshHeight, coordinates, offsets, transOffset, self.get_facecolor(), self._antialiased, self.get_edgecolors()) gc.restore() renderer.close_group(self.__class__.__name__) self.stale = False patchstr = artist.kwdoc(Collection) for k in ('QuadMesh', 'TriMesh', 'PolyCollection', 'BrokenBarHCollection', 'RegularPolyCollection', 'PathCollection', 'StarPolygonCollection', 'PatchCollection', 'CircleCollection', 'Collection',): docstring.interpd.update({k: patchstr}) docstring.interpd.update(LineCollection=artist.kwdoc(LineCollection))