{"action":"opened","issue":{"url":"https://api.github.com/repos/pyNLO/PyNLO/issues/30","repository_url":"https://api.github.com/repos/pyNLO/PyNLO","labels_url":"https://api.github.com/repos/pyNLO/PyNLO/issues/30/labels{/name}","comments_url":"https://api.github.com/repos/pyNLO/PyNLO/issues/30/comments","events_url":"https://api.github.com/repos/pyNLO/PyNLO/issues/30/events","html_url":"https://github.com/pyNLO/PyNLO/issues/30","id":153758414,"number":30,"title":"Assertion failure when using larger windows with more points","user":{"login":"hn-88","id":6321069,"avatar_url":"https://avatars.githubusercontent.com/u/6321069?v=3","gravatar_id":"","url":"https://api.github.com/users/hn-88","html_url":"https://github.com/hn-88","followers_url":"https://api.github.com/users/hn-88/followers","following_url":"https://api.github.com/users/hn-88/following{/other_user}","gists_url":"https://api.github.com/users/hn-88/gists{/gist_id}","starred_url":"https://api.github.com/users/hn-88/starred{/owner}{/repo}","subscriptions_url":"https://api.github.com/users/hn-88/subscriptions","organizations_url":"https://api.github.com/users/hn-88/orgs","repos_url":"https://api.github.com/users/hn-88/repos","events_url":"https://api.github.com/users/hn-88/events{/privacy}","received_events_url":"https://api.github.com/users/hn-88/received_events","type":"User","site_admin":false},"labels":[],"state":"open","locked":false,"assignee":null,"milestone":null,"comments":0,"created_at":"2016-05-09T11:43:57Z","updated_at":"2016-05-09T11:43:57Z","closed_at":null,"body":"I wanted to model ps pumped SCG over many metres of propagation. Thinking that running out of memory would be the bottleneck, I implemented an iterative script, saving the pulse-out to file after short lengths, and reading from it in the next iteration. Attached  \r\n[SCG-Head-by-parts2.py.txt](https://github.com/pyNLO/PyNLO/files/254844/SCG-Head-by-parts2.py.txt)\r\n\r\nBut I saw that the temporal pulse goes outside the 20 ps window when propagated for 20 metres, as in\r\n[SCG-Head-by-partsNL.py.txt](https://github.com/pyNLO/PyNLO/files/254848/SCG-Head-by-partsNL.py.txt)\r\n![figure](https://cloud.githubusercontent.com/assets/6321069/15111890/d0cc5b84-1607-11e6-928a-3ccada65bd1d.jpg)\r\nWanting to increase the time window, if I increase the time window by a factor of two and increase the number of points also by a factor of two, I start getting assertion failure errors.\r\n\r\n`\r\nTime taken so far - 0 hours 0 minutes 30 seconds\r\n30.3910000324\r\nIteration 2 of 2000\r\nPulse energy before NL-1050-NEG-1.txt : 11.9999464432 nJ\r\nTraceback (most recent call last):\r\n  File \"SCG-Head-by-partsNL2.py\", line 80, in <module>\r\n    y, AW, AT, pulse_out = evol.propagate(pulse_in=pulse, fiber=fiber1, n_steps=\r\nSteps)\r\n  File \"D:\\Anaconda\\lib\\site-packages\\pynlo\\interactions\\FourWaveMixing\\SSFM.py\"\r\n, line 485, in propagate\r\n    self.setup_fftw(pulse_in, fiber, output_power)\r\n  File \"D:\\Anaconda\\lib\\site-packages\\pynlo\\interactions\\FourWaveMixing\\SSFM.py\"\r\n, line 225, in setup_fftw\r\n    self.A[:]       = self.conditional_fftshift(pulse_in.AT, verify=True)\r\n  File \"D:\\Anaconda\\lib\\site-packages\\pynlo\\interactions\\FourWaveMixing\\SSFM.py\"\r\n, line 672, in conditional_fftshift\r\n    assert abs(chksum - np.sum(abs(x))) <= np.finfo(float).eps\r\nAssertionError `\r\n\r\n\r\nCan you help me avoid this problem? The file which gave this error is\r\n[SCG-Head-by-partsNL2.py.txt](https://github.com/pyNLO/PyNLO/files/254863/SCG-Head-by-partsNL2.py.txt)\r\nand it uses the dispersion from\r\n[NL-1050-NEG-1.txt](https://github.com/pyNLO/PyNLO/files/254865/NL-1050-NEG-1.txt)\r\n\r\n\r\n\r\n"}}