bash

To create rectangles of a solid color with bash, following script comes in handy. Save it in a file, e.g. createBlackRect.sh and run it with

bash /path/to/script/createBlackRect.sh

Here the script

For copying a bunch of files and excluding certain files, an easy tool to use is rsync. To exclude all .h5 files use following command

rsync -rv copy/all/from/this/path/* --exclude=*.h5 /path/Where/To/Copy

r = recursive (copies everything), v = verbose

1. Remove leading zeros

num=0004;
num=$(expr $num + 0)
echo $num;   # output: 4

2. subtract integers

num=3;
subtract=50;
numNew=$(( $num - $subtract));
echo $numNew; #result: -47

3. divide

num_half=$(expr $num / 2)

In the following some useful bash snippets to manipulat strings / file names are listed.

Extract substrings

1. crop a consecutive substring ${string:position:length}

name=abcd123FGHI;
subStr=${name:4:3};
echo $subStr; # result is 123

2. remove beginning or end of a string

str=/path/to/my/file/123_complicated_9034.txt;

removes shortest matching suffix pattern %

I included following lines into my ~/.bashrc to have a more secure shell experience.

1) Do not remove (unlink) a file, but move it to the trash-can. You have to install trash-cli,
 

sudo apt-get install trash-cli

alias rm="echo 'NOTE: !! not removing, but moving to trash-can!! '; trash-put"

If you want to use the normal rm command, use

/bin/rm file1ToRemove.txt file2ToRemove.png

2) ask before overwriting a file, if you accidentaly copy or move a file with the same name.

A list with examplary parameters of how to use the terminal function "find" (in Linux). This function can be used to find files, directories, etc. First open the terminal (Ctrl+Alt+t) and then type in one of the following commands.