Error Code 1 in PARDISO: zero or negative pivot

Asked By 30 points N/A Posted on -
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Hi,

MKL 10.1 is used to solve sparse linear system which is symmetric and positive definitely. But PARDISO foils with error code 1 giving the message” Error in PARDISO: zero or negative pivot, A is not SPD matrix” during phase 22.

If any one finds the reason of this error, please help me.

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Answered By 0 points N/A #152866

Error Code 1 in PARDISO: zero or negative pivot

qa-featured

Hello Carl,

You will need to  make sure that in C, you have specified iparm[26] = 1 because C uses zero based array indices. You will be able to see the output from the matrix checker in the event that there are errors. To do a test of that, you will need to present the first row of the matrix in unsorted order, something like the following:

Instead of having 1,2,3,4,6, you will need to give something like 1,2,3,6,4,

Once you do that you will see the following:

     *** Error in PARDISO  (incorrect input matrix  ) error_num= 24
     *** Input check: j=4, ja(j)=6, ja(j+1)=4 are incompatible

     ERROR during symbolic factorization: -1

Hope this helps.

Regards,

Carl

 

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