[NEST Users] Re: Random seed in NEST 3.0

Hi, I just did the following test with the current NEST master and NEST 3.1 and there things seem to work as expected. I get different membrane potentials for neurons with seeds 100 and 1000 when initializing on creation: In [*8*]: nest.ResetKernel() In [*9*]: nest.rng_seed = 100 In [*10*]: n = nest.Create('iaf_psc_alpha', 10, params={'V_m': nest.random.normal(-51., 10)}) In [*11*]: n.V_m Out[*11*]: (-48.59349994516202, -62.391924115381116, -41.373005254994425, -57.40416211886578, -55.00625628226899, -58.390425179047895, -55.24506539841326, -53.025705514351856, -51.605353014049754, -55.422455776310166) In [*12*]: nest.ResetKernel() In [*13*]: nest.rng_seed = 1000 In [*14*]: n = nest.Create('iaf_psc_alpha', 10, params={'V_m': nest.random.normal(-51., 10)}) In [*15*]: n.V_m Out[*15*]: (-61.99342803053577, -43.36557257654475, -56.96149010671454, -46.802621999699895, -38.1809073583283, -46.72672336036912, -52.65744001330793, -54.65343890518882, -45.195683344187955, -38.82283445344244) This also works as expected if I draw at the Python level In [*27*]: nest.ResetKernel() In [*28*]: nest.rng_seed = 100 In [*29*]: [nest.random.normal(-51., 10).GetValue() *for* _ *in* range(5)] Out[*29*]: [-49.30997769812133, -49.87958247942526, -49.81013407516723, -53.261688886622565, -57.7916578766182] In [*30*]: nest.ResetKernel() In [*31*]: nest.rng_seed = 1000 In [*32*]: [nest.random.normal(-51., 10).GetValue() *for* _ *in* range(5)] Out[*32*]: [-34.1615153889346, -31.487943150805098, -46.29074242569416, -49.91770982448142, -52.23367995498362] So it seems strange that it does not work for you. Is there any chance you have a mix of older versions? Could you delete all build and install directories and start from scratch (assuming you built NEST yourself; otherwise, how did you install NEST?). Best, Hans Ekkehard -- Prof. Dr. Hans Ekkehard Plesser Head, Department of Data Science Faculty of Science and Technology Norwegian University of Life Sciences PO Box 5003, 1432 Aas, Norway Phone +47 6723 1560 Email hans.ekkehard.plesser(a)nmbu.no Home http://arken.nmbu.no/~plesser On 24/11/2021, 18:08, "Maryada Maryada" &lt;er.maryada(a)gmail.com&gt; wrote: Hi Stine, I got the answer from your follow-up questions, So rng_type was default but it's interesting that NEST 3.0 does not really have any effect on randomization when I set rng_seed using nest.rng_seed but only if I use nest.SetKernalStatus..... if you run the following code import nest nest.ResetKernel() nest.rng_seed = 307 # nest.SetKernelStatus({'rng_seed': 33}) for _ in range(10): v_m = nest.random.normal(mean=-51., std=10.) print(v_m.GetValue()) print(nest.rng_seed) # print(nest.GetKernelStatus('rng_seed')) No matter what value you set for seed the out is always the same set of 10 values. and nest.rng_seed value is updated for different set values. However, It works if I use the old syntax. I am assuming it's not a bug but is what 3.1 offers and was added partially in 3.0 version already. On Wed, Nov 24, 2021 at 3:22 PM Stine Brekke Vennemo < stine.brekke.vennemo(a)nmbu.no&gt; wrote: Dear Maryada, Am I understanding you correctly that every time you call v_m.GetValue() you get the same results? I am not able to reproduce your results, I get a new value for V_m every time I switch rng_seed, and also if I call v_m.GetValue() a second time with the same seed without doing a ResetKernel. To test that you are actually setting a new rng seed, maybe do a print(nest.rng_seed) to make sure? What is your output if you type print(nest.rng_type)? Best wishes, Stine ------------------------------ *From:* Maryada Maryada &lt;er.maryada(a)gmail.com&gt; *Sent:* Monday, November 22, 2021 12:40 *To:* NEST User Mailing List &lt;users(a)nest-simulator.org&gt; *Subject:* [NEST Users] Random seed in NEST 3.0 Dear NEST users, As I understood from the documentation unless you set the seed using nest.rng_seed, nest.random.normal (for instance) should return the same value nest.ResetKernel() nest.rng_seed = 21#69696 v_m = nest.random.normal(mean=-51., std=10.) v_m.GetValue() In this code, I always receive the same v_m value for both cases, if the seed is set as 21 or 69696. The only time it changes is if I remove ResetKernel() call, which then is expected to return different values irrespective of rng_seed. With this code below, I also got the same results irrespective of rng_seed value nest.ResetKernel() nest.rng_seed = 3333#69696 for _ in range(10): v_m = nest.random.normal(mean=-51., std=10.) print(v_m.GetValue()) So, maybe rng_seed doesn't reflect on nest.random.normal distribution. However, then how can I make sure it draws a different set of values? -- Thanks and Regards *Maryada* _______________________________________________ NEST Users mailing list -- users(a)nest-simulator.org To unsubscribe send an email to users-leave(a)nest-simulator.org -- Thanks and Regards *Maryada* _______________________________________________ NEST Users mailing list -- users(a)nest-simulator.org To unsubscribe send an email to users-leave(a)nest-simulator.org