python-igraph API reference

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

class documentation

class Matrix:

View In Hierarchy

Simple matrix data type.

Of course there are much more advanced matrix data types for Python (for instance, the ndarray data type of Numeric Python) and this implementation does not want to compete with them. The only role of this data type is to provide a convenient interface for the matrices returned by the Graph object (for instance, allow indexing with tuples in the case of adjacency matrices and so on).

Class Method Fill Creates a matrix filled with the given value
Class Method Identity Creates an identity matrix.
Class Method Zero Creates a matrix filled with zeros.
Method __add__ Adds the given value to the matrix.
Method __eq__ Checks whether a given matrix is equal to another one
Method __getitem__ Returns a single item, a row or a column of the matrix
Method __hash__ Returns a hash value for a matrix.
Method __iadd__ In-place addition of a matrix or scalar.
Method __init__ Initializes a matrix.
Method __isub__ In-place subtraction of a matrix or scalar.
Method __iter__ Support for iteration.
Method __ne__ Checks whether a given matrix is not equal to another one
Method __plot__ Plots the matrix to the given Cairo context in the given box
Method __repr__ Undocumented
Method __setitem__ Sets a single item, a row or a column of the matrix
Method __str__ Undocumented
Method __sub__ Subtracts the given value from the matrix.
Method max Returns the maximum of the matrix along the given dimension
Method min Returns the minimum of the matrix along the given dimension
Instance Variable data Undocumented
Property shape Returns the shape of the matrix as a tuple
Method _get_data Returns the data stored in the matrix as a list of lists
Method _set_data Sets the data stored in the matrix
Instance Variable _data Undocumented
Instance Variable _ncol Undocumented
Instance Variable _nrow Undocumented
@classmethod
def Fill(cls, value, *args):

Creates a matrix filled with the given value

Parameters
valuethe value to be used
*argsUndocumented
shapethe shape of the matrix. Can be a single integer, two integers or a tuple. If a single integer is given here, the matrix is assumed to be square-shaped.
@classmethod
def Identity(cls, *args):

Creates an identity matrix.

Parameters
*argsUndocumented
shapethe shape of the matrix. Can be a single integer, two integers or a tuple. If a single integer is given here, the matrix is assumed to be square-shaped.
@classmethod
def Zero(cls, *args):

Creates a matrix filled with zeros.

Parameters
*argsUndocumented
shapethe shape of the matrix. Can be a single integer, two integers or a tuple. If a single integer is given here, the matrix is assumed to be square-shaped.
def __add__(self, other):

Adds the given value to the matrix.

Parameters
othereither a scalar or a matrix. Scalars will be added to each element of the matrix. Matrices will be added together elementwise.
Returns
the result matrix
def __eq__(self, other):

Checks whether a given matrix is equal to another one

def __getitem__(self, i):

Returns a single item, a row or a column of the matrix

Parameters
iif a single integer, returns the ith row as a list. If a slice, returns the corresponding rows as another Matrix object. If a 2-tuple, the first element of the tuple is used to select a row and the second is used to select a column.
def __hash__(self):

Returns a hash value for a matrix.

def __iadd__(self, other):

In-place addition of a matrix or scalar.

def __init__(self, data=None):

Initializes a matrix.

Parameters
datathe elements of the matrix as a list of lists, or None to create a 0x0 matrix.
def __isub__(self, other):

In-place subtraction of a matrix or scalar.

def __iter__(self):

Support for iteration.

This is actually implemented as a generator, so there is no need for a separate iterator class. The generator returns copies of the rows in the matrix as lists to avoid messing around with the internals. Feel free to do anything with the copies, the changes won't be reflected in the original matrix.

def __ne__(self, other):

Checks whether a given matrix is not equal to another one

def __plot__(self, context, bbox, palette, **kwds):

Plots the matrix to the given Cairo context in the given box

Besides the usual self-explanatory plotting parameters (context, bbox, palette), it accepts the following keyword arguments:

  • style: the style of the plot. boolean is useful for plotting matrices with boolean (True/False or 0/1) values: False will be shown with a white box and True with a black box. palette uses the given palette to represent numbers by colors, the minimum will be assigned to palette color index 0 and the maximum will be assigned to the length of the palette. None draws transparent cell backgrounds only. The default style is boolean (but it may change in the future). None values in the matrix are treated specially in both cases: nothing is drawn in the cell corresponding to None.
  • square: whether the cells of the matrix should be square or not. Default is True.
  • grid_width: line width of the grid shown on the matrix. If zero or negative, the grid is turned off. The grid is also turned off if the size of a cell is less than three times the given line width. Default is 1. Fractional widths are also allowed.
  • border_width: line width of the border drawn around the matrix. If zero or negative, the border is turned off. Default is 1.
  • row_names: the names of the rows
  • col_names: the names of the columns.
  • values: values to be displayed in the cells. If None or False, no values are displayed. If True, the values come from the matrix being plotted. If it is another matrix, the values of that matrix are shown in the cells. In this case, the shape of the value matrix must match the shape of the matrix being plotted.
  • value_format: a format string or a callable that specifies how the values should be plotted. If it is a callable, it must be a function that expects a single value and returns a string. Example: "%#.2f" for floating-point numbers with always exactly two digits after the decimal point. See the Python documentation of the % operator for details on the format string. If the format string is not given, it defaults to the str function.

If only the row names or the column names are given and the matrix is square-shaped, the same names are used for both column and row names.

def __repr__(self):

Undocumented

def __setitem__(self, i, value):

Sets a single item, a row or a column of the matrix

Parameters
iif a single integer, sets the ith row as a list. If a slice, sets the corresponding rows from another Matrix object. If a 2-tuple, the first element of the tuple is used to select a row and the second is used to select a column.
valuethe new value
def __str__(self):

Undocumented

def __sub__(self, other):

Subtracts the given value from the matrix.

Parameters
othereither a scalar or a matrix. Scalars will be subtracted from each element of the matrix. Matrices will be subtracted together elementwise.
Returns
the result matrix
def max(self, dim=None):

Returns the maximum of the matrix along the given dimension

Parameters
dimthe dimension. 0 means determining the column maximums, 1 means determining the row maximums. If None, the global maximum is returned.
def min(self, dim=None):

Returns the minimum of the matrix along the given dimension

Parameters
dimthe dimension. 0 means determining the column minimums, 1 means determining the row minimums. If None, the global minimum is returned.
data =

Undocumented

@property
shape =

Returns the shape of the matrix as a tuple

def _get_data(self):

Returns the data stored in the matrix as a list of lists

def _set_data(self, data=None):

Sets the data stored in the matrix

_data =

Undocumented

_ncol =

Undocumented

_nrow =

Undocumented