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Dear All,</div>
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I am seeking to perform a large number of eigenvalue calculations (related to a fluid dynamics</div>
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problem) using the slepc framework. I have written the program that calls slepc and validated its solutions against </div>
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known results for special cases - the Jacobi-Davidson iteration seemed to perform best on this problem.</div>
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Since in the 'production-level' calculation I will step through a parameter space which should </div>
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mean only small changes to the eigenproblem between each calculation,<b> it seems to make sense</b></div>
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<b> to use the previous solution as the initial guess for the next calculation.</b></div>
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The sequence to execute this strategy would seem to be:</div>
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To write out the current soln subspace:</div>
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call EPSGetInvariantSubspace<br>
[ call VecView -> binary file (if a file storage is required for possible restart)]</div>
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To then read in this data to use it as the initial subspace for the next run:</div>
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call EPSSetInitialSpace</div>
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My question is that EPSGetInvariantSubspace needs an 'array of nconv vectors', <b>
how does one create</b></div>
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<b> such an array</b> ? My understanding is that the Vec structure is just a one-dimensional array (with contents </div>
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possibly scattered in non-contiguous memory locations !?) , so do we just need to create a long Vec </div>
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that stores multiple vectors ? How can we do this (the examples I have seen thus far use a MatCreateVecs to specify the size</div>
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of the Vec)?</div>
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If loading such a subspace from a binary file (created maybe by VecView), presumably VecLoad is the</div>
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best way to load such an array of vectors from the binary file ?</div>
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Best wishes and many thanks,</div>
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Dan.</div>
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