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  • pycodegen
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  • !49

Actually increment counter inside random_symbol

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Merged Michael Kuron requested to merge random_symbol into master Sep 04, 2019
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@RudolfWeeber is currently looking at the statistical mechanics of the fluctuating LB and found a velocity bias. It turned out that this is due to all generated random numbers using the same key. Instead it should be incremented when generating multiple random numbers in the same kernel.

So in the generated code,

philox_float4(time_step, ctr_0, ctr_1, ctr_2, 0, 2, Dummy_38, Dummy_39, Dummy_40, Dummy_41);
philox_float4(time_step, ctr_0, ctr_1, ctr_2, 0, 2, Dummy_34, Dummy_35, Dummy_36, Dummy_37);
philox_float4(time_step, ctr_0, ctr_1, ctr_2, 0, 2, Dummy_30, Dummy_31, Dummy_32, Dummy_33);
philox_float4(time_step, ctr_0, ctr_1, ctr_2, 0, 2, Dummy_26, Dummy_27, Dummy_28, Dummy_29);

becomes

philox_float4(time_step, ctr_0, ctr_1, ctr_2, 3, 2, Dummy_38, Dummy_39, Dummy_40, Dummy_41);
philox_float4(time_step, ctr_0, ctr_1, ctr_2, 2, 2, Dummy_34, Dummy_35, Dummy_36, Dummy_37);
philox_float4(time_step, ctr_0, ctr_1, ctr_2, 1, 2, Dummy_30, Dummy_31, Dummy_32, Dummy_33);
philox_float4(time_step, ctr_0, ctr_1, ctr_2, 0, 2, Dummy_26, Dummy_27, Dummy_28, Dummy_29);
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Source branch: random_symbol