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MATLAB Function Reference Volume 1: A - E - Bad Request

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colmmd<br />

2-280<br />

0<br />

100<br />

200<br />

300<br />

400<br />

0 100 200 300 400<br />

nz = 1887<br />

A<br />

Comparing the spy plot of the LU factorization of the original matrix with that<br />

of the reordered matrix shows that minimum degree reduces the time and<br />

storage requirements by better than a factor of 2.8. The nonzero counts are<br />

16777 and 5904, respectively.<br />

spy(lu(A))<br />

spy(lu(A(:,p)))<br />

0<br />

100<br />

200<br />

300<br />

400<br />

lu(A)<br />

0 100 200 300 400<br />

nz = 16777<br />

0<br />

100<br />

200<br />

300<br />

400<br />

A(:,p)<br />

0 100 200 300 400<br />

nz = 1887<br />

0<br />

100<br />

200<br />

300<br />

400<br />

lu(A(:,p))<br />

0 100 200 300 400<br />

nz = 5904

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