pyyeti.locate.mat_intersect

pyyeti.locate.mat_intersect(D1, D2, keep=0)

Get row intersection partition vectors between two matrices or vectors.

Parameters:

• D1 (array_like) – 1d or 2d array.

• D2 (array_like) – 1d or 2d array.

• keep (integer) –

  0, 1 or 2:

  • if 0, loop over smaller matrix, finding where the rows occur in the larger

  • if 1, loop over D1, finding where the rows occur in D2

  • if 2, loop over D2, finding where the rows occur in D1

Returns:

• pv1 (1d ndarray) – Row index vector into D1.

• pv2 (1d ndarray) – Row index vector into D2.

Notes

pv1 and pv2 are found such that:

D1[pv1] == D2[pv2]
(Note for matrices:  M[i] == M[i, :])

For matrices, the number of columns in D1 and D2 must be equal to get non-empty results.

Examples

>>> import numpy as np
>>> from pyyeti import locate
>>> mat1 = np.array([[7, 3], [6, 8], [4, 0], [9, 2], [1, 5]])
>>> mat2 = np.array([[9, 2], [1, 5], [7, 3]])
>>> pv1, pv2 = locate.mat_intersect(mat1, mat2)
>>> pv1
array([3, 4, 0]...)
>>> pv2
array([0, 1, 2]...)
>>> np.all(mat1[pv1] == mat2[pv2])
True
>>> locate.mat_intersect(mat1, mat2, 1)
(array([0, 3, 4]...), array([2, 0, 1]...))
>>> locate.mat_intersect(mat2, mat1, 2)
(array([2, 0, 1]...), array([0, 3, 4]...))
>>> locate.mat_intersect(mat2, mat1)
(array([0, 1, 2]...), array([3, 4, 0]...))
>>> mat3 = np.array([[1, 2, 3]])
>>> locate.mat_intersect(mat1, mat3)
(array([], dtype=int...), array([], dtype=int...)