Path: csiph.com!fu-berlin.de!uni-berlin.de!not-for-mail From: Robert Kern Newsgroups: comp.lang.python Subject: Re: Question about figure plot Date: Tue, 15 Dec 2015 15:22:14 +0000 Lines: 63 Message-ID: References: Mime-Version: 1.0 Content-Type: text/plain; charset=utf-8; format=flowed Content-Transfer-Encoding: 7bit X-Trace: news.uni-berlin.de X25i7cJ/MYSqb18snTMuZwQflds1BmT+7GledHIx4Rwg== Return-Path: X-Original-To: python-list@python.org Delivered-To: python-list@mail.python.org X-Spam-Status: OK 0.000 X-Spam-Evidence: '*H*': 1.00; '*S*': 0.00; 'essentially': 0.04; 'defaults': 0.05; 'subject:Question': 0.05; 'api': 0.09; 'pyplot': 0.09; 'received:80.91': 0.09; 'received:80.91.229': 0.09; 'received:gmane.org': 0.09; 'received:list': 0.09; 'script,': 0.09; 'subject:plot': 0.09; 'underlying': 0.09; 'assume': 0.11; 'def': 0.13; 'alpha': 0.15; '(note:': 0.16; 'kern': 0.16; 'numpy': 0.16; 'received:80.91.229.3': 0.16; 'received:io': 0.16; 'received:plane.gmane.org': 0.16; 'received:psf.io': 0.16; 'url:faq': 0.16; 'wrote:': 0.16; 'figures': 0.18; 'windows': 0.20; 'skip:v 30': 0.20; 'interpret': 0.22; 'code,': 0.23; 'import': 0.24; 'examples': 0.24; 'header:In-Reply-To:1': 0.24; 'header :User-Agent:1': 0.26; 'header:X-Complaints-To:1': 0.26; 'figure': 0.27; 'right.': 0.27; 'function': 0.28; 'raise': 0.29; 'run': 0.33; 'attempt': 0.35; 'robert': 0.35; 'skip:p 30': 0.35; 'there': 0.36; 'url:org': 0.36; 'lines': 0.36; 'to:addr:python-list': 0.36; 'subject:: ': 0.37; 'two': 0.37; 'received:org': 0.37; 'no,': 0.38; 'skip:p 20': 0.38; 'hi,': 0.38; 'means': 0.39; 'to:addr:python.org': 0.40; 'some': 0.40; 'skip:n 10': 0.62; 'different': 0.63; 'our': 0.64; 'world': 0.64; 'believe': 0.66; 'here': 0.66; 'url:index': 0.67; 'eco': 0.84; 'modes:': 0.84; 'terrible': 0.84; 'choice.': 0.93 X-Injected-Via-Gmane: http://gmane.org/ X-Gmane-NNTP-Posting-Host: uk.enthought.com User-Agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10.11; rv:38.0) Gecko/20100101 Thunderbird/38.4.0 In-Reply-To: X-BeenThere: python-list@python.org X-Mailman-Version: 2.1.20+ Precedence: list List-Id: General discussion list for the Python programming language List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Xref: csiph.com comp.lang.python:100463 On 2015-12-15 02:43, Robert wrote: > Hi, > > When I run the following code, there is no figure shown in the end. > > > ////////// > import pymc > import numpy as np > > n = 5*np.ones(4,dtype=int) > x = np.array([-.86,-.3,-.05,.73]) > > alpha = pymc.Normal('alpha',mu=0,tau=.01) > beta = pymc.Normal('beta',mu=0,tau=.01) > > @pymc.deterministic > def theta(a=alpha, b=beta): > """theta = logit^{-1}(a+b)""" > return pymc.invlogit(a+b*x) > > d = pymc.Binomial('d', n=n, p=theta, value=np.array([0.,1.,3.,5.]),\ > observed=True) > .... > import pymc > import mymodel > > S = pymc.MCMC(mymodel, db='pickle') > S.sample(iter=10000, burn=5000, thin=2) > pymc.Matplot.plot(S) > > > > I find that the figures are shown after these two lines by myself: > ************* > import matplotlib.pyplot as plt > plt.show() > > I have searched around and have not found some explanation about it. > The plot function here is different from Matlab's. Is there better ways than > my last two lines? (I am not confident whether my last two lines is the > only choice. No, that's right. pymc.Matplot.plot() uses matplotlib's pyplot API underneath. pyplot can run in two different modes: interactive and non-interactive. When used in a standalone script, like I assume here, it defaults to non-interactive. That means that it will not raise any plot windows until you call plt.show(). http://matplotlib.org/faq/usage_faq.html#what-is-interactive-mode See any of the examples here (note: "pylab" is the essentially the same as "pyplot" for these purposes): http://matplotlib.org/examples/pylab_examples/index.html -- Robert Kern "I have come to believe that the whole world is an enigma, a harmless enigma that is made terrible by our own mad attempt to interpret it as though it had an underlying truth." -- Umberto Eco