A number of linear algebra functions are available as sub-module
linalg of numpy.
np.linalg.det(a)
Returns the determinant of a 2-d array .
a
>>> m = np.array(((2,3), (-1, -2))) >>> print m [[ 2 3] [-1 -2]] >>> print np.linalg.det(m) -1.0
np.linalg.inv(a)
Returns the matrix inverse of a non-singular 2-d array
.
a
>>> good = np.array(((2.1, 3.2), (4.3, 5.4))) >>> print np.linalg.inv(good) [[-2.23140496 1.32231405] [ 1.7768595 -0.8677686 ]]
np.linalg.norm(a)
Returns the Frobenius norm of array .
a
>>> print good [[ 2.1 3.2] [ 4.3 5.4]] >>> print np.linalg.norm(good) 7.89303490427
np.linalg.solve(A,
b)
Solves systems of simultaneous linear equations.
Given an N×N array of coefficients , and a
length-N vector of constants A, returns a length-N vector
containing the solved values of the variables.
b
Here's an example system:
2x + y = 19
x - 2y = 2
Here's a conversational example showing the solution (x=8 and y=3):
>>> coeffs = np.array([[2,1], [1,-2]]) >>> print coeffs [[ 2 1] [ 1 -2]] >>> consts = np.array((19, 2)) >>> print consts [19 2] >>> print np.linalg.solve(coeffs, consts) [ 8. 3.]