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Version 3.0.2.post1751+g2658eef4f
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matplotlib.backends.backend_svg

matplotlib.backends.backend_svg.FigureCanvas

alias of matplotlib.backends.backend_svg.FigureCanvasSVG

class matplotlib.backends.backend_svg.FigureCanvasSVG(figure)[source]

Bases: matplotlib.backend_bases.FigureCanvasBase

filetypes = {'svg': 'Scalable Vector Graphics', 'svgz': 'Scalable Vector Graphics'}
fixed_dpi = 72
get_default_filetype()[source]

Get the default savefig file format as specified in rcParam savefig.format. Returned string excludes period. Overridden in backends that only support a single file type.

print_svg(filename, *args, **kwargs)[source]
print_svgz(filename, *args, **kwargs)[source]
class matplotlib.backends.backend_svg.RendererSVG(width, height, svgwriter, basename=None, image_dpi=72)[source]

Bases: matplotlib.backend_bases.RendererBase

close_group(s)[source]

Close a grouping element with label s

Only used by the SVG renderer.

draw_gouraud_triangle(gc, points, colors, trans)[source]

Draw a Gouraud-shaded triangle.

Parameters:
points : array_like, shape=(3, 2)

Array of (x, y) points for the triangle.

colors : array_like, shape=(3, 4)

RGBA colors for each point of the triangle.

transform : matplotlib.transforms.Transform

An affine transform to apply to the points.

draw_gouraud_triangles(gc, triangles_array, colors_array, transform)[source]

Draws a series of Gouraud triangles.

Parameters:
points : array_like, shape=(N, 3, 2)

Array of N (x, y) points for the triangles.

colors : array_like, shape=(N, 3, 4)

Array of N RGBA colors for each point of the triangles.

transform : matplotlib.transforms.Transform

An affine transform to apply to the points.

draw_image(gc, x, y, im, transform=None)[source]

Draw an RGBA image.

Parameters:
gc : GraphicsContextBase

a graphics context with clipping information.

x : scalar

the distance in physical units (i.e., dots or pixels) from the left hand side of the canvas.

y : scalar

the distance in physical units (i.e., dots or pixels) from the bottom side of the canvas.

im : array_like, shape=(N, M, 4), dtype=np.uint8

An array of RGBA pixels.

transform : matplotlib.transforms.Affine2DBase

If and only if the concrete backend is written such that option_scale_image() returns True, an affine transformation may be passed to draw_image(). It takes the form of a Affine2DBase instance. The translation vector of the transformation is given in physical units (i.e., dots or pixels). Note that the transformation does not override x and y, and has to be applied before translating the result by x and y (this can be accomplished by adding x and y to the translation vector defined by transform).

draw_markers(gc, marker_path, marker_trans, path, trans, rgbFace=None)[source]

Draws a marker at each of the vertices in path. This includes all vertices, including control points on curves. To avoid that behavior, those vertices should be removed before calling this function.

This provides a fallback implementation of draw_markers that makes multiple calls to draw_path(). Some backends may want to override this method in order to draw the marker only once and reuse it multiple times.

Parameters:
gc : GraphicsContextBase

The graphics context

marker_trans : matplotlib.transforms.Transform

An affine transform applied to the marker.

trans : matplotlib.transforms.Transform

An affine transform applied to the path.

draw_path(gc, path, transform, rgbFace=None)[source]

Draws a Path instance using the given affine transform.

draw_path_collection(gc, master_transform, paths, all_transforms, offsets, offsetTrans, facecolors, edgecolors, linewidths, linestyles, antialiaseds, urls, offset_position)[source]

Draws a collection of paths selecting drawing properties from the lists facecolors, edgecolors, linewidths, linestyles and antialiaseds. offsets is a list of offsets to apply to each of the paths. The offsets in offsets are first transformed by offsetTrans before being applied. offset_position may be either "screen" or "data" depending on the space that the offsets are in.

This provides a fallback implementation of draw_path_collection() that makes multiple calls to draw_path(). Some backends may want to override this in order to render each set of path data only once, and then reference that path multiple times with the different offsets, colors, styles etc. The generator methods _iter_collection_raw_paths() and _iter_collection() are provided to help with (and standardize) the implementation across backends. It is highly recommended to use those generators, so that changes to the behavior of draw_path_collection() can be made globally.

draw_tex(gc, x, y, s, prop, angle, ismath='TeX!', mtext=None)[source]
draw_text(gc, x, y, s, prop, angle, ismath=False, mtext=None)[source]

Draw the text instance.

Parameters:
gc : GraphicsContextBase

The graphics context.

x : scalar

The x location of the text in display coords.

y : scalar

The y location of the text baseline in display coords.

s : str

The text string.

prop : matplotlib.font_manager.FontProperties

The font properties.

angle : scalar

The rotation angle in degrees.

mtext : matplotlib.text.Text

The original text object to be rendered.

Notes

backend implementers note

When you are trying to determine if you have gotten your bounding box right (which is what enables the text layout/alignment to work properly), it helps to change the line in text.py:

if 0: bbox_artist(self, renderer)

to if 1, and then the actual bounding box will be plotted along with your text.

finalize()[source]
flipy()[source]

Return whether y values increase from top to bottom.

Note that this only affects drawing of texts and images.

get_canvas_width_height()[source]

Return the canvas width and height in display coords.

get_image_magnification()[source]

Get the factor by which to magnify images passed to draw_image(). Allows a backend to have images at a different resolution to other artists.

get_text_width_height_descent(s, prop, ismath)[source]

Get the width, height, and descent (offset from the bottom to the baseline), in display coords, of the string s with FontProperties prop

open_group(s, gid=None)[source]

Open a grouping element with label s and gid (if set) as id.

Only used by the SVG renderer.

option_image_nocomposite()[source]

Return whether image composition by Matplotlib should be skipped.

Raster backends should usually return False (letting the C-level rasterizer take care of image composition); vector backends should usually return not rcParams["image.composite_image"].

option_scale_image()[source]

Return whether arbitrary affine transformations in draw_image() are supported (True for most vector backends).

class matplotlib.backends.backend_svg.XMLWriter(file)[source]

Bases: object

Parameters:
file : writable text file-like object
close(id)[source]

Closes open elements, up to (and including) the element identified by the given identifier.

Parameters:
id

Element identifier, as returned by the start() method.

comment(comment)[source]

Adds a comment to the output stream.

Parameters:
comment : str

Comment text.

data(text)[source]

Adds character data to the output stream.

Parameters:
text : str

Character data.

element(tag, text=None, attrib={}, **extra)[source]

Adds an entire element. This is the same as calling start(), data(), and end() in sequence. The text argument can be omitted.

end(tag=None, indent=True)[source]

Closes the current element (opened by the most recent call to start()).

Parameters:
tag

Element tag. If given, the tag must match the start tag. If omitted, the current element is closed.

flush()[source]

Flushes the output stream.

start(tag, attrib={}, **extra)[source]

Opens a new element. Attributes can be given as keyword arguments, or as a string/string dictionary. The method returns an opaque identifier that can be passed to the close() method, to close all open elements up to and including this one.

Parameters:
tag

Element tag.

attrib

Attribute dictionary. Alternatively, attributes can be given as keyword arguments.

Returns:
An element identifier.
matplotlib.backends.backend_svg.escape_attrib(s)[source]
matplotlib.backends.backend_svg.escape_cdata(s)[source]
matplotlib.backends.backend_svg.escape_comment(s)[source]
matplotlib.backends.backend_svg.generate_css(attrib={})[source]
matplotlib.backends.backend_svg.generate_transform(transform_list=[])[source]
matplotlib.backends.backend_svg.short_float_fmt(x)[source]

Create a short string representation of a float, which is %f formatting with trailing zeros and the decimal point removed.