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Computes the Eigenvectors of a square table without a preliminary balancing step.
NBEIGVEC(a)
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a |
- |
A square matrix. |
A square table of the same dimensions as the input table. Each column of the output table is an Eigenvector. The Eigenvector in column n of NBEIGVEC corresponds to the Eigenvalue in row n of NBEIGVAL .
W1: {{8i, 0, 1+i},
{ 0, 1001, 0+3i},
{90, 0+i, 200}}
nbeigvec(W1) ==
{{-0.911 + 0.048i, -0.006 – 0.005i, 0.000 – 0.000i},
{ 0.000 – 0.001i, 0.000 + 0.004i, -1.000 – 0.005i},
{ 0.409 – 0.006i, -1.090 + 0.096i, 0.000 – 0.001i}}
EIGVAL and EIGVEC first perform a balancing step in which the rows and columns are transformed to have root mean squares as close as possible while leaving the Eigenvalues and Eigenvectors unchanged. In most cases, this improves the accuracy of EIGVAL and EIGVEC, but in some cases it does not. BALANCE can be used to check that relatively small table elements have not become unduly magnified by the balancing step. If they have, then NBEIGVAL and NBEIGVEC are likely to yield better results.