alias of FigureCanvasSVG

class matplotlib.backends.backend_svg.FigureCanvasSVG(figure=None)[source]#

Bases: FigureCanvasBase


Render the Figure.

This method must walk the artist tree, even if no output is produced, because it triggers deferred work that users may want to access before saving output to disk. For example computing limits, auto-limits, and tick values.

filetypes = {'svg': 'Scalable Vector Graphics', 'svgz': 'Scalable Vector Graphics'}#
fixed_dpi = 72#

Return the default savefig file format as specified in rcParams["savefig.format"] (default: 'png').

The returned string does not include a period. This method is overridden in backends that only support a single file type.

print_svg(filename, *, bbox_inches_restore=None, metadata=None)[source]#
filenamestr or path-like or file-like

Output target; if a string, a file will be opened for writing.

metadatadict[str, Any], optional

Metadata in the SVG file defined as key-value pairs of strings, datetimes, or lists of strings, e.g., {'Creator': 'My software', 'Contributor': ['Me', 'My Friend'], 'Title': 'Awesome'}.

The standard keys and their value types are:

  • str: 'Coverage', 'Description', 'Format', 'Identifier', 'Language', 'Relation', 'Source', 'Title', and 'Type'.

  • str or list of str: 'Contributor', 'Creator', 'Keywords', 'Publisher', and 'Rights'.

  • str, date, datetime, or tuple of same: 'Date'. If a non-str, then it will be formatted as ISO 8601.

Values have been predefined for 'Creator', 'Date', 'Format', and 'Type'. They can be removed by setting them to None.

Information is encoded as Dublin Core Metadata.

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

Bases: RendererBase


Close a grouping element with label s.

Only used by the SVG renderer.

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

[Deprecated] Draw a Gouraud-shaded triangle.


The graphics context.

points(3, 2) array-like

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

colors(3, 4) array-like

RGBA colors for each point of the triangle.


An affine transform to apply to the points.


Deprecated since version 3.7: Use draw_gouraud_triangles instead.

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

Draw a series of Gouraud triangles.


The graphics context.

triangles_array(N, 3, 2) array-like

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

colors_array(N, 3, 4) array-like

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


An affine transform to apply to the points.

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

Draw an RGBA image.


A graphics context with clipping information.


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


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

im(N, M, 4) array of numpy.uint8

An array of RGBA pixels.


If and only if the concrete backend is written such that option_scale_image returns True, an affine transformation (i.e., an Affine2DBase) may be passed to draw_image. 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]#

Draw a marker at each of path's vertices (excluding control points).

The base (fallback) implementation makes multiple calls to draw_path. Backends may want to override this method in order to draw the marker only once and reuse it multiple times.


The graphics context.


The path for the marker.


An affine transform applied to the marker.


The locations to draw the markers.


An affine transform applied to the path.

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

Draw a Path instance using the given affine transform.

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

Draw a collection of paths.

Each path is first transformed by the corresponding entry in all_transforms (a list of (3, 3) matrices) and then by master_transform. They are then translated by the corresponding entry in offsets, which has been first transformed by offset_trans.

facecolors, edgecolors, linewidths, linestyles, and antialiased are lists that set the corresponding properties.

offset_position is unused now, but the argument is kept for backwards compatibility.

The base (fallback) implementation makes multiple calls to draw_path. 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_text(gc, x, y, s, prop, angle, ismath=False, mtext=None)[source]#

Draw a text instance.


The graphics context.


The x location of the text in display coords.


The y location of the text baseline in display coords.


The text string.


The font properties.


The rotation angle in degrees anti-clockwise.

ismathbool or "TeX"

If True, use mathtext parser. If "TeX", use tex for rendering.


The original text object to be rendered.


Note for backend implementers:

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

if 0: bbox_artist(self, renderer)

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


Return whether y values increase from top to bottom.

Note that this only affects drawing of texts.


Return the canvas width and height in display coords.


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.

Whitespace at the start and the end of s is included in the reported width.

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.


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"].


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

filewritable text file-like object

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


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


Add a comment to the output stream.


Comment text.


Add character data to the output stream.


Character data.

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

Add 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]#

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


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

indentbool, default: True

Flush the output stream.

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

Open 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.


Element tag.


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

An element identifier.