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--></style></head><body lang=EN-US link=blue vlink="#954F72"><div class=WordSection1><p class=MsoNormal>If you want to use the same entropy-initialized generator for temporarily-reproducible experiments, then you can use</p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal>gen = np.random.default_rng()</p><p class=MsoNormal>state = gen.bit_generator.state</p><p class=MsoNormal>gen.standard_normal()</p><p class=MsoNormal># 0.5644742559549797, will vary across runs</p><p class=MsoNormal>gen.bit_generator.state = state</p><p class=MsoNormal>gen.standard_normal()</p><p class=MsoNormal># Always the same as before 0.5644742559549797</p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal>The equivalent to the old way of calling seed to reseed is:</p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal>SEED = 918273645</p><p class=MsoNormal>gen = np.random.default_rng(SEED)</p><p class=MsoNormal>gen.standard_normal()</p><p class=MsoNormal># 0.12345677<o:p></o:p></p><p class=MsoNormal>gen = np.random.default_rng(SEED)<o:p></o:p></p><p class=MsoNormal>gen.standard_normal()<o:p></o:p></p><p class=MsoNormal># Identical value</p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal>Rather than reseeding the same object, you just create a new object. At some point in the development of Generator both methods were timed and there was no performance to reusing the same object by reseeding.</p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal>Kevin</p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal><o:p> </o:p></p><div style='mso-element:para-border-div;border:none;border-top:solid #E1E1E1 1.0pt;padding:3.0pt 0in 0in 0in'><p class=MsoNormal style='border:none;padding:0in'><b>From: </b><a href="mailto:ndbecker2@gmail.com">Neal Becker</a><br><b>Sent: </b>Monday, June 29, 2020 1:01 PM<br><b>To: </b><a href="mailto:numpy-discussion@python.org">Discussion of Numerical Python</a><br><b>Subject: </b>Re: [Numpy-discussion] reseed random generator (1.19)</p></div><p class=MsoNormal><o:p> </o:p></p><div><p class=MsoNormal>I was using this to reset the generator, in order to repeat the same sequence again for testing purposes.</p></div><p class=MsoNormal><o:p> </o:p></p><div><div><p class=MsoNormal>On Wed, Jun 24, 2020 at 6:40 PM Robert Kern <<a href="mailto:robert.kern@gmail.com">robert.kern@gmail.com</a>> wrote:</p></div><blockquote style='border:none;border-left:solid #CCCCCC 1.0pt;padding:0in 0in 0in 6.0pt;margin-left:4.8pt;margin-right:0in'><div><div><p class=MsoNormal>On Wed, Jun 24, 2020 at 3:31 PM Neal Becker <<a href="mailto:ndbecker2@gmail.com" target="_blank">ndbecker2@gmail.com</a>> wrote:</p></div><div><blockquote style='border:none;border-left:solid #CCCCCC 1.0pt;padding:0in 0in 0in 6.0pt;margin-left:4.8pt;margin-right:0in'><div><div><p class=MsoNormal>Consider the following:</p></div><div><p class=MsoNormal><o:p> </o:p></p></div><p class=MsoNormal>from numpy.random import default_rng<br>rs = default_rng()</p><div><p class=MsoNormal><o:p> </o:p></p></div><div><p class=MsoNormal>Now how do I re-seed the generator?</p></div><div><p class=MsoNormal>I thought perhaps rs.bit_generator.seed(), but there is no such attribute.</p></div></div></blockquote><div><p class=MsoNormal><o:p> </o:p></p></div><div><p class=MsoNormal>In general, reseeding an existing generator instance is not a good practice. What effect are you trying to accomplish? I assume that you are asking this because you are currently using `RandomState.seed()`. In what circumstances?</p></div><div><p class=MsoNormal><o:p> </o:p></p></div><div><p class=MsoNormal>The raw `bit_generator.state` property *can* be assigned to, in order to support some advanced use cases (mostly involving de/serialization and similar kinds of meta-programming tasks). It's also been helpful for me to construct worst-case scenarios for testing parallel streams. But it quite deliberately bypasses the notion of deriving the state from a human-friendly seed number.</p></div><div><p class=MsoNormal> </p></div></div><p class=MsoNormal>-- </p><div><p class=MsoNormal>Robert Kern</p></div></div><p class=MsoNormal>_______________________________________________<br>NumPy-Discussion mailing list<br><a href="mailto:NumPy-Discussion@python.org" target="_blank">NumPy-Discussion@python.org</a><br><a href="https://mail.python.org/mailman/listinfo/numpy-discussion" target="_blank">https://mail.python.org/mailman/listinfo/numpy-discussion</a></p></blockquote></div><p class=MsoNormal><br clear=all></p><div><p class=MsoNormal><o:p> </o:p></p></div><p class=MsoNormal>-- </p><p class=MsoNormal><i>Those who don't understand recursion are doomed to repeat it</i></p><p class=MsoNormal><o:p> </o:p></p></div></body></html>