Vim sudo write

" Allow saving of files as sudo when I forgot to start vim using sudo.
cmap w!! w !sudo tee > /dev/null %

Awk remove duplicate lines

http://stackoverflow.com/questions/2604088/awk-remove-line-if-field-is-duplicate

Javascript, clone array

   

Jiggery pokery to copy the data, useful, but not here
    http://stackoverflow.com/questions/3865139/cast-javascript-object-to-array-how-to#answer-3865808
   
    var d = $.extend(true,{},arrel);
    d.length = arrel.length;
    var dd = Array.prototype.slice.call(d);

Remove lines from file 1 that are in fiel 2

grep -v -x -f f2 f1 should do the trick.

With some explanations:

-v for select non-matching lines
-x for matching whole lines only
-f f2 to get patterns from f2.

sgrep like a player

Used to remove nodes with a given colour from a SVG file

 sgrep -i 'inner("<"..">") not containing ("#00ffff" or "#ff00ff" or "#ff0000")' < survey_plain.svg > survey_really_plain.svg

Create favico using GIMP

Take image,
make sure Image > Mode RGB is selected.

Scale to 32x32

Save as GIF (indexed using default settings)

Save a copy as Microsoft Windows Icon and choose bpp. 4 Worked nicely last time.

Stop VIM scrolling two viewports simultaneously:
:set scb!

Keyword:scrollbind

Python Adventures Part 1

Add path using shell variable PYTHONPATH

then load module of your file (i.e. survey.py)

Must reload this everytime a change is made using reload(survey). Ugh.

To fix this, go to ipython and 

import ipy_autoreload. 

Then run 

%autoreload 2

 (other behaviours given by %autoreload ?)

To read csv, import numpy and then use function recfromscv

to get help with functions, import the module and type help(module.function)

To automatically make all things in a module accessible just do 

from module import *

Bash no clobber

either set noclobber to 0 or just use >| instead of >

Amazing tilable textures!

http://webtreats.mysitemyway.com

Remove Encryption from PDF

for i in *.pdf; do gs -q -dNOPAUSE -dBATCH -sDEVICE=pdfwrite -sOutputFile=${i%%.*}_unen.pdf -c .setpdfwrite -f $i; done;

Vim automatic system clipboard

set guioptions+=a

SVN add project

svn import . path/to/repository

Make Matlab writable by pipes

mkfifo matin

Matpipe:
#!/bin/bash
((tail -f ~/matin | tee >(cat 1>&2)) & cat) | matlab

Writemat
#!/bin/bash
cat $@ | tee ~/matin

Vim function
vmap :call ExecuteMatlab()
function! ExecuteMatlab() range
:'<,'>!writemat
endfunction


Then pipe commands to matin.

This prints stuff sent to matin to the stdin of matlab and also to stderr, as well as able to read from the stdin of the terminal.

Keyword: process substitution - >(....) creates a temporary file in bash and feeds stuff to that process.

Save wrong line bash

A simple thing to do when you realize you just typed the wrong line is hit Ctrl+C; if you want to keep the line, but need to execute something else first, begin a new line with a back slash - \, then Ctrl+C. The line will remain in your history.

Latex Dashes

Hyphen: daughter-in-law, X-rated\\
En dash: pages 13--67\\
Em dash: yes---or no? \\
Minus sign: $0$, $1$ and $-1$

Bash trim filename

However, buried in there is a section on Parameter Substitution which tells us that $foo is really a shorthand for ${foo} which is really the simplest case of several ${foo:operators} and similar constructs.

Given:
foo=/tmp/my.dir/filename.tar.gz

We can use these expressions:

path = ${foo%/*}

To get: /tmp/my.dir (like dirname)

file = ${foo##*/}

To get: filename.tar.gz (like basename)

base = ${file%%.*}

To get: filename

ext = ${file#*.}

To get: tar.gz



${variable%pattern}
Trim the shortest match from the end
${variable##pattern}
Trim the longest match from the beginning
${variable%%pattern}
Trim the longest match from the end
${variable#pattern}
Trim the shortest match from the beginning

Beep frequency

xset b vol freq dur

volume: % of max
freq: Hz
dur: ms

Reverse Tunelling and x2x

To control a box behind a firewall using keyboard and mouse on another computer.

On firewalled computer run

ssh -R 22222:localhost:22 user@localcomp

On local computer run
ssh -p -X 22222 user@localhost
In the last ssh tunnel run

x2x -east -to :0

Gvim invisible cursor after vsplit

Vim code:

let &guifont=&guifont

From:
http://old.nabble.com/Cursor-become-invisible.-td20630223.html