Page - 4 - in Programming for Computations – Python - A Gentle Introduction to Numerical Simulations with Python 3.6, Volume Second Edition

4 1 TheFirstFewSteps Somecomputerscience terms Note that,quiteoften, the termsscript andscriptingareusedassynonymsfor programandprogramming,respectively. The inventor of the Perl programming language, Larry Wall, tried to explain the difference between script and program in a humorousway (from perl.coma): Suppose you went back to Ada Lovelaceb and asked her the differencebetweenascript anda program.She’dprobably lookat you funny, then say something like: Well, a script is what you give the actors, but a programiswhatyougive theaudience.ThatAdawasonesharp lady...Since her time, we seem to have gotten a bit more confused about what we mean whenwesayscripting. It confusesevenme,andI’msupposedtobeoneof the experts. There are many other widely used computer science terms to pick up as well.Forexample,writingaprogram(orscript orcode) isoftenexpressedas implementing theprogram.Executinga programmeans runningtheprogram. A default value is what will be used if nothing is specified. An algorithm is a recipe for how to construct a program. A bug is an error in a program, and the art of tracking down and removing bugs is called debugging (see, e.g.,Wikipediac).Simulatingorsimulationrefers tousingaprogramtomimic processes in the real world, often through solving differential equations that govern the physics of the processes. A plot is a graphical representation of a data set. For example, if you walk along a straight road, recording your position y with time t, say every second, your data set will consist of pairs with correspondingy and t values. With two perpendicular axes in a plane (e.g., a computer screen or a sheet of paper), one “horizontal” axis for t and one“vertical”axisfory,eachpairofpointscouldbemarkedinthatplane.The axesand the pointsmake up a plot, which represents the data set graphically. Usually, suchplotting isdonebya computer. a http://www.perl.com/pub/2007/12/06/soto-11.html. b http://en.wikipedia.org/wiki/Ada_Lovelace. c http://en.wikipedia.org/wiki/Software_bug#Etymology. 1.1.1 InstallingPython Tostudythisbook,youneedaPythoninstallationthatfits thepurpose.Thequickest way to get a useful Python installationon yourWindows,Mac, orLinuxcomputer, is to download and install Anaconda.2 There are alternatives (as you can find on the internet), but we have had very good experiences with Anaconda for several years, so that is our first choice. No separate installation of Python or Spyder (our recommended environment for writing Python code) is then required, as they are both included inAnaconda. 2 https://www.anaconda.com/distribution.