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Hi, I just tried to run varmin_linjas with a large expansion in u (6 params), chi (6 params) and f(4x4 params) (discerning spin-same and spin-different coefficients). However, the program stops execution, without giving me any further information:
Performing variance minimization using Varmin_linjas
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Number of linear parameters in Jastrow : 264
G arrays allocated with size : 4.62 GiB
Number of configs loaded : 10080
Can varmin_linjas not handle this any more, because there are too many parameters? (I succeeded in doing a smaller varmin_linjas calculation)

Dear Katharina,

The varmin-linjas method scales as O(P^4), where P is the number of parameters (and the arrays get correspondingly large). I recently fixed an integer overflow that could occur in varmin-linjas with huge numbers of parameters.

I would be cautious about using varmin-linjas for more than, say, 100-150 parameters, because the way in which the least-squares function is evaluated is susceptible to rounding errors.

264 parameters is a very large number of linear parameters... I think you should try to reduce this if possible.

Best wishes,

Neil.