Path: csiph.com!newsfeed.hal-mli.net!feeder3.hal-mli.net!news.stack.nl!newsfeed.xs4all.nl!newsfeed2.news.xs4all.nl!xs4all!post.news.xs4all.nl!not-for-mail Return-Path: X-Original-To: python-list@python.org Delivered-To: python-list@mail.python.org X-Spam-Status: OK 0.005 X-Spam-Evidence: '*H*': 0.99; '*S*': 0.00; 'python.': 0.02; 'anyway.': 0.05; 'subject:Python': 0.06; 'amtsgericht': 0.07; 'explicit': 0.07; 'hrb': 0.07; 'subject:file': 0.07; 'assuming': 0.09; 'way:': 0.09; '24,': 0.16; 'equation': 0.16; 'liu': 0.16; 'rainer': 0.16; 'ralf': 0.16; 'subject: \n ': 0.16; 'subject:array': 0.16; 'subject:integration': 0.16; 'wrote:': 0.18; 'all,': 0.19; 'gmbh': 0.22; 'python?': 0.22; 'header:User-Agent:1': 0.23; 'integrate': 0.24; 'subject:like': 0.24; 'germany': 0.24; 'question': 0.24; 'help!': 0.26; 'second': 0.26; 'values': 0.27; 'header:In-Reply- To:1': 0.27; 'that.': 0.31; 'integrating': 0.31; 'phone:': 0.31; 'file': 0.32; 'but': 0.35; 'thanks': 0.36; 'possible': 0.36; 'integration': 0.37; 'two': 0.37; 'to:addr:python-list': 0.38; 'to:addr:python.org': 0.39; 'mailing': 0.39; 'easy': 0.60; 'first': 0.61; 'email addr:gmail.com': 0.63; 'received:194': 0.64; 'subject:The': 0.64; 'sum': 0.64; 'more': 0.64; 'skip:+ 10': 0.65; 'dear': 0.65; 'tel.:': 0.65; 'below:': 0.68; 'containing': 0.69; 'press': 0.70; 'respect': 0.70; 'equation,': 0.84; 'received:192.168.57': 0.84; 'do:': 0.91 Date: Fri, 16 May 2014 17:01:04 +0200 From: Johannes Schneider User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:24.0) Gecko/20100101 Icedove/24.5.0 MIME-Version: 1.0 To: python-list@python.org Subject: Re: The possibility integration in Python without an equation, just an array-like file References: In-Reply-To: Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 8bit X-BeenThere: python-list@python.org X-Mailman-Version: 2.1.15 Precedence: list List-Id: General discussion list for the Python programming language List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Newsgroups: comp.lang.python Message-ID: Lines: 63 NNTP-Posting-Host: 2001:888:2000:d::a6 X-Trace: 1400254020 news.xs4all.nl 2955 [2001:888:2000:d::a6]:58789 X-Complaints-To: abuse@xs4all.nl Xref: csiph.com comp.lang.python:71664 If you do not have a closed form for T(E) you cannot calculate the exact value of I(V). Anyway. Assuming T is integrable you can approximate I(V). 1. Way to do: interpolate T(E) by a polynomial P and integrate P. For this you need the equation (coefficients and exponents) of P. Integrating is easy after that. 2. other way: Use Stair-functions: you can approximate the Value of IV() by the sum over T(E_i) * (E_{i+1} - E_i) s.t. E_0 = E_F-\frac{eV}{2} and E_n = E_F+\frac{eV}{2}. 3 one more way: use a computer algebra system like sage. bg, Johannes On 16.05.2014 10:49, Enlong Liu wrote: > Dear All, > > I have a question about the integration with Python. The equation is as > below: > and I want to get values of I with respect of V. E_F is known. But for > T(E), I don't have explicit equation, but a .dat file containing > two columns, the first is E, and the second is T(E). It is also in the > attachment for reference. So is it possible to do integration in Python? > > Thanks a lot for your help! > > Best regards, > ​ > > -- > Faculty of Engineering@K.U. Leuven > BIOTECH@TU Dresden > Email:liuenlong20@gmail.com ; > enlong.liu@student.kuleuven.be ; > enlong.liu@biotech.tu-dresden.de > Mobile Phone: +4917666191322 > Mailing Address: Zi. 0108R, Budapester Straße 24, 01069, Dresden, Germany > > -- Johannes Schneider Webentwicklung johannes.schneider@galileo-press.de Tel.: +49.228.42150.xxx Galileo Press GmbH Rheinwerkallee 4 - 53227 Bonn - Germany Tel.: +49.228.42.150.0 (Zentrale) .77 (Fax) http://www.galileo-press.de/ Geschäftsführer: Tomas Wehren, Ralf Kaulisch, Rainer Kaltenecker HRB 8363 Amtsgericht Bonn