W4DPSAS: not positive definite algorithm

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W4DPSAS: not positive definite algorithm

#1 Post by Biswamoy_Paul » Mon Aug 26, 2019 5:02 am

I am running W4DPSAS for the northern Indian Ocean with UKMO-EN4 obs. For a simulation of 5 days with 50 inner loops and 1 outer loop, I am getting the error:

Code: Select all

 CONGRAD - Fatal error, not possitive definite algorithm:

           cg_delta = -5.76565447E+09   (001, 022)
at the end of TLM for loop inner=22. Does this imply that the matrix corresponding to the conjugate gradient algorithm is not positive definite?! How can I solve this issue? This set-up has no balance operator.

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