(a ROUGH DRAFT of something I'm considering for my linear algebra class next semester...)
Every week you'll have an assignment intended to help you acquire and practice skills and concepts that are, well, foundational to the study of linear algebra. The ideas, procedures, and calculations in these assignments are essential to success in this course.
| # Sage has a built-in rref() method for matrices, but sometimes when | |
| # teaching it's nice to get a list of the row operations you would do to | |
| # put the matrix into rref -- or, equivalent, a list of the | |
| # corresponding elementary matrices. | |
| # | |
| # This script contains two functions along those lines: | |
| # | |
| # rref(): returns a list of elementary matrices that put the matrix into rref | |
| # rref_steps(): returns a list of strings that describe what row ops to do | |
| # |
| """ | |
| I use duplicity to back up my files, and cron sends me an email every | |
| day with the output from the backup. Sometimes the size of an | |
| incremental backup is unusually large, and I wonder what made it so big. | |
| This script takes a .difftar.gpg or .sigtar.gpg file and prints the | |
| names of the files in it, listed in decreasing order by size. There's no | |
| error checking of any kind. Enjoy! | |
| Usage: |
| """ | |
| Permalinks from the Sage cell server [1] include the Sage code in the URL, | |
| and sometimes you may want to get that Sage code without loading the URL | |
| in a browser. | |
| The get_sage_code function does exactly that. It's basically copied from | |
| web_server.py [2]. Just feed it the full URL and it returns the Sage | |
| code. | |
| The get_urls function is the inverse. It is essentially stolen from line |
| """ | |
| My Newton's method Sage @interact. A reworked version of | |
| http://wiki.sagemath.org/interact/calculus#Newton-Raphson_Root_Finding | |
| by Neal Holtz, and which was in turn inspired by Marshall Hampton's | |
| tangent line grapher. | |
| This code is available as a published worksheet at | |
| https://sagenb.kaist.ac.kr:8066/home/pub/53 and on the Sage cell server at | |
| http://aleph.sagemath.org/?q=81e86e25-b27c-40c6-ac01-b7489b55e84e. (Note | |
| that right now, you need to use |
| ;; add this to your .emacs / init.el to use mmm (multiple major modes) with SageTeX. This works with AUCTeX and | |
| ;; emacs 23.4. The fontification gets a little wonky, though; quotes inside a SageTeX environment throw | |
| ;; off the highlighting for the LaTeX bits that follow. But the modes correctly get switched. | |
| ;; if you don't have sage-mode installed, you can either (1) do "sage -i sage-mode" and follow the instructions to | |
| ;; enable it, or (2) replace sage-mode below with python-mode, which is good enough for regular editing of Sage code | |
| (require 'mmm-auto) | |
| (setq mmm-global-mode 'maybe) |
| /* Like join.c, but I want to see if multiple threads can wait on a single | |
| condition. It looks like `pthread_cond_broadcast` is the API function for this. | |
| What's weird is that this has some kind of race condition in it. I've seen: | |
| * only the parent woken up | |
| * parent and child2 woken up | |
| * child2 woken up twice! | |
| */ |
| ;; This is originally from | |
| ;; http://ubuntuforums.org/showthread.php?s=618526e60dfcf25e6413439603fa08ad&t=1716268&page=2. | |
| ;; Thanks to user "florenzen". I've included the fixes for Ubuntu 11.10 | |
| ;; and wrapped buffer-file-name in a call to file-truename because | |
| ;; kpathsea/SyncTeX follow symlinks; see | |
| ;; http://tex.stackexchange.com/questions/25578/why-is-synctex-in-tl-2011-so-fussy-about-filenames. | |
| ;; Forward/inverse search with evince using D-bus. | |
| (if (require 'dbus "dbus" t) | |
| (progn |
| select * from THINGS_IM_GONNA_DO where | |
| thing = "give you up" or | |
| thing = "let you down" or | |
| thing = "run around and desert you" or | |
| thing = "make you cry" or | |
| thing = "say goodbye" or | |
| thing = "tell a lie and hurt you"; | |
| select count(*) from problems; | |
| 99 |