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question about number of eigenvalues found w/ dfeast_scsrev

Gagan
Beginner
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hi guys,

 

just curious about the 'm' integer when using feast.

currently i know what the 'bottom eigenvector' will be (it's the unit vector with eigenvalue 0), so i specify the last eigenvector to ensure the correct solution is found.

in the end, the eigensolver finds exactly one less than the total number of eigenvalues being requested. i.e. if i request 151 eigenvectors, and i've specified the bottom one, it says 150 eigenvectors are found.

i just want to ensure that this behaviour is correct, as it seems i have 151 total eigenvectors (150 of which were 'found', the last of which was a 'guess'). 

 

 

 

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