SNOPT options: major iterations limit

[crist...@gmail.com]

Hi,

I am solving a nonlinear model with SNOPT and I get that the optimizer reaches the major iterations limit. This option is not included in the options that I can input to SNOPT with "options snopt_options" AMPL interface. Nevertheless, this option can be modified with a SNOPT specs file. Does anyone know how to input a SNOPT spec file in AMPL?

Thank you very much.

Cristian Hernandez 

[Michael Saunders]

Hi Cristian,

My understanding is that any options in a specs file can be

including in the options statement.  For example:

   options snopt_options  '\

      major_iterations=500 \

      scale_option=0          \

      LU_factor_tol=2.0     \

';

Good luck,

Michael

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[victor.z...@gmail.com]

Hi Cristian,

You should be able to set the number of iterations via the iterations option as described here:

  option snopt_options 'iterations=200';

HTH,

Victor

--

[Michael Saunders]

Hi again Cristian,

Victor's example is in agreement.

I wanted to add that for convenience you can use * as a comment character:

   options snopt_options  '\

      major_iterations=500 \

      scale_option=0          \

      *LU_factor_tol=2.0     \

';

This comments out the last option.

Michael