Opened 9 years ago

Closed 20 months ago

#10 closed defect (migrated)

Sparse jacobian: inf's and nan's in non-zero values array

Reported by: ad007804 Owned by: awalther
Priority: major Component: libadolc
Version: Keywords: sparce jacobian



I am a new user of the ADOL-C library.

I am trying to solve the jacobian of a residual function in my structured CFD solver. In my application, I have 5 dependent variables and roughly 1700 independent variables. The number of non-zero values in the jacobian matrix is roughly 200, hence the usage of the sparse_jac driver.

The jacobian driver works perfectly fine, but I obtain inf's and nan's in the non-zeros values array. Note that the row and column index arrays are fine when compared to the entire matrix output of the jacobian driver. I tried changing the option array without success.

I was using version 2.3.0 and recently upgraded to 4.3.1 with the same behavior.

Can you please help me with my problem? Thank you for your time, Antoine

Change History (3)

comment:1 Changed 9 years ago by ad007804

BTW, I am using colpack version 1.0.9.

comment:2 Changed 9 years ago by ad007804

Me again!

I solved my problem by changing the following:

WAS: pow(fabs(spi)),zeta);

IS: pow(fabs(spi)+epsilon,zeta);

Is this a best practice I should apply for all fabs?

comment:3 Changed 20 months ago by stefan

  • Resolution set to migrated
  • Status changed from new to closed

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