python-igraph API reference

List of all classes, functions and methods in python-igraph

class documentation

class CairoPlot:

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Class representing an arbitrary plot that uses the Cairo plotting backend.

Objects that you can plot include graphs, matrices, palettes, clusterings, covers, and dendrograms.

In Cairo, every plot has an associated surface object. The surface is an instance of cairo.Surface, a member of the pycairo library. The surface itself provides a unified API to various plotting targets like SVG files, X11 windows, PostScript files, PNG files and so on. igraph does not usually know on which surface it is plotting at each point in time, since pycairo takes care of the actual drawing. Everything that's supported by pycairo should be supported by this class as well.

Current Cairo surfaces include:

  • cairo.GlitzSurface -- OpenGL accelerated surface for the X11 Window System.
  • cairo.ImageSurface -- memory buffer surface. Can be written to a PNG image file.
  • cairo.PDFSurface -- PDF document surface.
  • cairo.PSSurface -- PostScript document surface.
  • cairo.SVGSurface -- SVG (Scalable Vector Graphics) document surface.
  • cairo.Win32Surface -- Microsoft Windows screen rendering.
  • cairo.XlibSurface -- X11 Window System screen rendering.

If you create a Plot object with a string given as the target surface, the string will be treated as a filename, and its extension will decide which surface class will be used. Please note that not all surfaces might be available, depending on your pycairo installation.

A Plot has an assigned default palette (see igraph.drawing.colors.Palette) which is used for plotting objects.

A Plot object also has a list of objects to be plotted with their respective bounding boxes, palettes and opacities. Palettes assigned to an object override the default palette of the plot. Objects can be added by the Plot.add method and removed by the Plot.remove method.

Method __init__ Creates a new plot.
Instance Variable bbox Undocumented
Property background Returns the background color of the plot. None means a transparent background.
Method add Adds an object to the plot.
Method background.setter No summary
Method remove Removes an object from the plot.
Method mark_dirty Marks the plot as dirty (should be redrawn)
Method redraw Redraws the plot
Method save Saves the plot.
Property bounding_box Returns the bounding box of the Cairo surface as a BoundingBox object
Property height Returns the height of the Cairo surface on which the plot is drawn
Property surface Returns the Cairo surface on which the plot is drawn
Property width Returns the width of the Cairo surface on which the plot is drawn
Instance Variable _filename Undocumented
Instance Variable _need_tmpfile Undocumented
Instance Variable _palette Undocumented
Instance Variable _surface Undocumented
Instance Variable _ctx Undocumented
Instance Variable _objects Undocumented
Instance Variable _is_dirty Undocumented
Instance Variable _background Undocumented
Method _repr_svg_ Returns an SVG representation of this plot as a string.
def __init__(self, target=None, bbox=None, palette=None, background=None):

Creates a new plot.

Parameterstargetthe target surface to write to. It can be one of the following types:
  • None -- a Cairo surface will be created and the object will be plotted there.
  • cairo.Surface -- the given Cairo surface will be used.
  • string -- a file with the given name will be created and an appropriate Cairo surface will be attached to it.
bboxthe bounding box of the surface. It is interpreted differently with different surfaces: PDF and PS surfaces will treat it as points (1 point = 1/72 inch). Image surfaces will treat it as pixels. SVG surfaces will treat it as an abstract unit, but it will mostly be interpreted as pixels when viewing the SVG file in Firefox.
palettethe palette primarily used on the plot if the added objects do not specify a private palette. Must be either an igraph.drawing.colors.Palette object or a string referring to a valid key of igraph.drawing.colors.palettes (see module igraph.drawing.colors) or None. In the latter case, the default palette given by the configuration key plotting.palette is used.
backgroundthe background color. If None, the background will be transparent. You can use any color specification here that is understood by igraph.drawing.colors.color_name_to_rgba.
_filename =

Undocumented

_need_tmpfile =

Undocumented

(type: bool)
bbox =

Undocumented

_palette =

Undocumented

_surface =

Undocumented

_ctx =

Undocumented

_objects =

Undocumented

(type: list)
_is_dirty =

Undocumented

(type: bool)
@property
background =

Returns the background color of the plot. None means a transparent background.

def add(self, obj, bbox=None, palette=None, opacity=1.0, *args, **kwds):

Adds an object to the plot.

Arguments not specified here are stored and passed to the object's plotting function when necessary. Since you are most likely interested in the arguments acceptable by graphs, see Graph.__plot__ for more details.

Parametersobjthe object to be added
bboxthe bounding box of the object. If None, the object will fill the entire area of the plot.
palettethe color palette used for drawing the object. If the object tries to get a color assigned to a positive integer, it will use this palette. If None, defaults to the global palette of the plot.
opacitythe opacity of the object being plotted, in the range 0.0-1.0
argsUndocumented
kwdsUndocumented
See AlsoGraph.__plot__
@background.setter
def background(self, color):

Sets the background color of the plot. None means a transparent background. You can use any color specification here that is understood by the get method of the current palette or by igraph.drawing.colors.color_name_to_rgb.

_background =

Undocumented

def remove(self, obj, bbox=None, idx=1):

Removes an object from the plot.

If the object has been added multiple times and no bounding box was specified, it removes the instance which occurs idxth in the list of identical instances of the object.

Parametersobjthe object to be removed
bboxoptional bounding box specification for the object. If given, only objects with exactly this bounding box will be considered.
idxif multiple objects match the specification given by obj and bbox, only the idxth occurrence will be removed.
ReturnsTrue if the object has been removed successfully, False if the object was not on the plot at all or idx was larger than the count of occurrences
def mark_dirty(self):

Marks the plot as dirty (should be redrawn)

def redraw(self, context=None):

Redraws the plot

def save(self, fname=None):

Saves the plot.

Parametersfnamethe filename to save to. It is ignored if the surface of the plot is not an ImageSurface.
def _repr_svg_(self):

Returns an SVG representation of this plot as a string.

This method is used by IPython to display this plot inline.

@property
bounding_box =

Returns the bounding box of the Cairo surface as a BoundingBox object

@property
height =

Returns the height of the Cairo surface on which the plot is drawn

@property
surface =

Returns the Cairo surface on which the plot is drawn

@property
width =

Returns the width of the Cairo surface on which the plot is drawn

API Documentation for python-igraph, generated by pydoctor 21.2.2 at 2021-10-18 16:23:19.