class: middle, center # The SageMath system [Sage Days 75](http://wiki.sagemath.org/days75) 8/22/2016 [](http://www.sagemath.org/) .license[  [Public Domain](http://creativecommons.org/publicdomain/zero/1.0/) ] --- class:middle, center # SageMath ? --- # The SageMath mission > "Creating a viable free open source alternative to Magma, Maple, Mathematica and Matlab. > > [...] > > and a welcoming community of users and developers" --- # SageMath's founding principles - Developed by teachers, researchers and professionals, for teachers, researchers and students. - Free (as in freedom, GPL) - "We are building the car, not reinventing the wheel" - ATLAS, GAP, Linbox, Maxima, MPFR, MPIR, PARI/GP, NetworkX, NTL, Numpy/Scipy, Singular, Symmetrica, ... - Standard programming language (Python) - Standard notebook system ([IPython](http://tmpnb.org)) - "Bazar" development model - Active proselytism --- class:middle, center # [Demo](https://cloud.sagemath.com/projects/a8436f67-cdc5-4f3f-bf97-363d6be83c3d/files/) --- # Sage is a free software distribution ## Software included with SageMath: <iframe src="http://www.sagemath.org/links-components.html#sage-nav" style="overflow-y:scroll;height:400px;width:100%"> </iframe> --- # Sage is a free software distribution ~~~ > sage -gap ┌───────┐ GAP 4.8.3, 19-Mar-2016, build of 2016-04-06 16:18:27 (CEST) │ GAP │ http://www.gap-system.org └───────┘ Architecture: x86_64-unknown-linux-gnu-gcc-default64 Libs used: gmp, readline Loading the library and packages ... Packages: GAPDoc 1.5.1 Try '?help' for help. See also '?copyright' and '?authors' gap> ~~~ --- # Sage is a free software distribution ~~~ > sage -singular SINGULAR / Development A Computer Algebra System for Polynomial Computations / version 3-1-7 0< by: W. Decker, G.-M. Greuel, G. Pfister, H. Schoenemann \ Aug 2013 FB Mathematik der Universitaet, D-67653 Kaiserslautern \ > ~~~ --- # Sage is a free software distribution ~~~ > sage -maxima ;;; Loading #P"/home/defeo/sage/local/lib/ecl/sb-bsd-sockets.fas" ;;; Loading #P"/home/defeo/sage/local/lib/ecl/sockets.fas" ;;; Loading #P"/home/defeo/sage/local/lib/ecl/defsystem.fas" ;;; Loading #P"/home/defeo/sage/local/lib/ecl/cmp.fas" Maxima 5.35.1 http://maxima.sourceforge.net using Lisp ECL 16.1.2 Distributed under the GNU Public License. See the file COPYING. Dedicated to the memory of William Schelter. The function bug_report() provides bug reporting information. (%i1) ~~~ --- # Sage is a free software distribution ~~~ > sage -gp GP/PARI CALCULATOR Version 2.8.0 (development git-b70b447) amd64 running linux (x86-64/GMP-5.1.3 kernel) 64-bit version compiled: Aug 5 2016, gcc version 4.9.3 (GCC) threading engine: single (readline v6.3 enabled, extended help enabled) Copyright (C) 2000-2016 The PARI Group PARI/GP is free software, covered by the GNU General Public License, and comes WITHOUT ANY WARRANTY WHATSOEVER. Type ? for help, \q to quit. Type ?15 for how to get moral (and possibly technical) support. parisize = 8000000, primelimit = 500000 ~~~ --- # Sage is a free software distribution ~~~ > sage -R R version 3.2.4 Revised (2016-03-16 r70336) -- "Very Secure Dishes" Copyright (C) 2016 The R Foundation for Statistical Computing Platform: x86_64-pc-linux-gnu (64-bit) R is free software and comes with ABSOLUTELY NO WARRANTY. You are welcome to redistribute it under certain conditions. Type 'license()' or 'licence()' for distribution details. Natural language support but running in an English locale R is a collaborative project with many contributors. Type 'contributors()' for more information and 'citation()' on how to cite R or R packages in publications. Type 'demo()' for some demos, 'help()' for on-line help, or 'help.start()' for an HTML browser interface to help. Type 'q()' to quit R. > ~~~ --- # SageMath is a Python library SageMath also contains original code, implementing unique functionalities. - 2 Mlocs¹ - 51K commits² - 3.6K classes³ - 68K functions⁴ - rich mathematical content: categories, combinatorics, graphs, number theory, ... - many *exclusive* algorithms <small> ¹ Source: `wc -l $(find src/sage)`. ² Source: [GitHub](https://github.com/sagemath/sage). ³ Source: `grep -r ^class src/sage | wc -l`. ⁴ Source: `egrep -r '^\s*c?p?def' src/sage | wc -l`. </small> --- # SageMath has many different UIs - Command line, via IPython - Browser-based WebUI (Sage Notebook, *to disappear?*) - Browser-based WebUI ([Jupyter](https://jupyter.org/)) - Cloud service: http://cloud.sagemath.org - HTML5 widget ([Sage cells](https://sagecell.sagemath.org/)) - [emacs mode](http://wiki.sagemath.org/sage-mode) --- # [SageMath is portable](http://www.sagemath.org/download.html) Native versions for: - Most Linux distros - Solaris (32 et 64 bits) - FreeBSD - Most Mac OSX Also available on Windows - via a WebUI - in a virtual machine - in Cygwin or MinGW - on a bootable [usb key](http://sagedebianlive.metelu.net/) - via a [Docker image](https://github.com/sagemath/docker-images) (experimental, see also <https://github.com/embray/sage-windows>) --- # SageMath mini-history - 1999-2005: "William Stein writes over 25,000 lines of Magma code for his research, and realizes that Magma was a bad long term investment since he couldn't see or modify the internals." - Feb. 2005: Sage 0.1, a Python library linking PARI, Maxima, Python, Singular, GAP. - Fev. 2006: Sage 1.0 Sage Days 1, San Diego, 10 participants? - Fev. 2010: Sage 4.4.2 Sage Days 20, Luminy (France), 120 participants - Current version: SageMath 7.3 --- class:middle, center # Free as in *freedom* --- # Free as in *freedom* > “You can read Sylow’s Theorem and its proof in Huppert's book in the > library... then you can use Sylow’s Theorem for the rest of your > life free of charge, but for many computer algebra systems license > fees have to be paid regularly... With this situation two of > the most basic rules of conduct in mathematics are violated: In > mathematics information is passed on free of charge and everything > is laid open for checking.” > > — J. Neubüser (1993) (started GAP in 1986) --- # Freedom to run On any machine, for any (legal) use. ## Freedom to give away copies (Also to sell them!) Why? - (kind of) easy to install and maintain at your university - Students can use at home - Run computations remotely, scale freely - Share programs, notebooks - Free for anyone, even with limited resources - No costs for developing countries --- # Freedom to study the code Open source: you can read what it does Why? - Pedagogy - Dissemination - Expressive, readable, (kind of) well documented code - Reproducibility of scientific results - Verify (simple) proofs - Master hypotheses, models, algorithms - Analyze bugs and weird behaviors --- # Freedom to contribute Why? - Fix bugs - Write documentation - Write localizations - Domain specific development - Share code - Engage with a community --- # Some free books ### Calcul Mathématique avec Sage (in French) <http://sagebook.gforge.inria.fr/> ### The SageMath tutorial <http://www.sagemath.org/doc> David Joyner, William Stein et al. ### A First Course in Linear Algebra <http://linear.ups.edu> Robert Beezer ### More... <http://www.sagemath.org/library-publications.html#books> --- class:middle, center # Development model --- # `SageMath == Python` Python is an interpreted multi-paradigm programming language Easy to use, like a pocket calculator ~~~ python: x = 17 python: x 17 python: 3*x 51 ~~~ Easy to read and write: math: {17x | x ∈ {0, 1,... , 9} and x is odd } python: `{ 17*x for x in range(10) if x%2 == 1 }` --- # Python is extremely popular - Among the 5 most used programming languages > “Google has made no secret of the fact they use Python a lot for a >number of internal projects. Even knowing that, once I was an >employee, I was amazed at how much Python code there actually is in >the Google source code system.” > > — Guido van Rossum (créateur de Python) - Many libraries available in Python: data bases, graphics, network, parallel computing... - Easy to interface with C/C++/Fortran - Cython: Python ↔ C - Python has become a *de facto* standard in scientific computing. --- # Development cycle ### Bug tracking <http://trac.sagemath.org/> ### Tickets et patches Example : [Beginner tickets](https://trac.sagemath.org/query?status=needs_info&status=needs_review&status=needs_work&status=new&order=priority&col=id&col=summary&col=status&col=type&col=priority&col=milestone&col=component&keywords=%7Ebeginner&report=38) ### Release cycle A new version approximately every three months.