scipy tutorial - Baustatik-Info-Server

SciPy Reference Guide, Release 0.8.dev
v : double or complex double array, shape (M, M)
The normalized eigenvector corresponding to the eigenvalue w[i] is the column v[:,i].
Raises LinAlgError if eigenvalue computation does not converge :
eigvals_banded(a_band, lower=0, overwrite_a_band=0, select=’a’, select_range=None)
Solve real symmetric or complex hermitian band matrix eigenvalue problem.
Find eigenvalues w of a:
a v[:,i] = w[i] v[:,i]
v.H v = identity
The matrix a is stored in ab either in lower diagonal or upper diagonal ordered form:
ab[u + i - j, j] == a[i,j] (if upper form; i = j)
Example of ab (shape of a is (6,6), u=2):
upper form:
* * a02 a13 a24 a35
* a01 a12 a23 a34 a45
a00 a11 a22 a33 a44 a55
lower form:
a00 a11 a22 a33 a44 a55
a10 a21 a32 a43 a54 *
a20 a31 a42 a53 * *
Cells marked with * are not used.
Parameters
a_band : array, shape (M, u+1)
Banded matrix whose eigenvalues to calculate
lower : boolean
Is the matrix in the lower form. (Default is upper form)
overwrite_a_band: :
Discard data in a_band (may enhance performance)
select: {‘a’, ‘v’, ‘i’} :
Which eigenvalues to calculate
select calculated
‘a’ All eigenvalues
‘v’ Eigenvalues in the interval (min, max]
‘i’ Eigenvalues with indices min