Scripting on Bilal Syed Hussain

Viewing .csv files on the command line

bilalshussain@gmail.com (Bilal Syed Hussain) — Sat, 31 Oct 2015 16:46:31 +0000

It can be convenient to view a .csv file from the command line, when using SSH connection for example. A basic version with no dependencies is as follows:

function see_csv(){
    column -s, -t <"$1" | less --shift 2  -SN
}

with example output:

1 seq    run_no  kind        iterations  timeout
2 12001  1       undirected  64          600
3 12002  1       nsample     64          600

To handle blank fields we can use sed to add extra spaces for use with column:

function see_csv(){
    cat "$1" | sed 's/,,/, ,/g;s/,,/, ,/g' | column -s, -t | less --shift 2 -SN
}

If the .csv has many columns, you change the less options to the following:

function see_csv(){
    cat "$1" | sed 's/,,/, ,/g;s/,,/, ,/g' | column -s, -t | less -SN -Xs
}

So that the columns that can fit on the screen are printed, for convenience.

❯ see_csv experiment.csv
      1 seq    run_no  kind        iterations param timeout  
      2 16001  1       undirected  64               38400            
      3 16002  1       nsample     64               38400            
      4 16003  1       undirected  64               38400            

~/Desktop/Results/
❯

~/Desktop/Results/
❯

To access any addition columns use the arrow keys, this will cause the screen to be redrawn.

Alfred Extensions

bilalshussain@gmail.com (Bilal Syed Hussain) — Fri, 29 Mar 2013 00:15:21 +0000

Workflows and Extensions for Alfred hosted on https://github.com/Bilalh/AlfredExtensions

iTunes Ratings

Allows you to set the rating of the currently playing song. Support halves stars and empty ratings

based off https://github.com/qlassiqa/qWorkflow/tree/master/example%20workflows

Toggle Extension

A file action which toggles the visibility of file extensions for the selected files

Shellmarks

Allow the use of Shellmarks, a shell script that allows you to save and jump to commonly used directories from Alfred.

Pipe output from command line tools to a text editor

bilalshussain@gmail.com (Bilal Syed Hussain) — Sun, 22 Apr 2012 22:01:23 +0000

A useful feature is to pipe the result of a command such as ls to a text editor. This can be done by using:

	ls | open -f

Using the -a flag for open makes this even more useful allowing you to specify the application to open the output in e.g to open in TextMate use:

	ls | open -f -a Textmate

Shellmarks - terminal directory bookmarks

bilalshussain@gmail.com (Bilal Syed Hussain) — Sat, 14 Jan 2012 00:57:33 +0000

shellmarks is a shell script that allows you to save and jump to commonly used directories.

Usage Example

$ cd /var/www/
$ s web
$ cd /usr/local/bin/
$ s localbin
$ l
    web          /var/www/
    localbin     /usr/local/bin/
$ g web<tab>
$ g web          # cd to /var/www/
$ o web     	 # Open in Finder if on a mac

Extra Features

if no bookmark name is specified the default directory is used instead ($HOME unless changed)

cd ~/projects
s
g              # g now defaults to ~/projects

Commands can be placed after the bookmark

$ g web ls     # cd to ~/home/projects/www/ then executes ls
~/var/www/
index.html
site.css
$

cd like features

g -   # does cd -
g ..  # does cd ..
g /   # does cd /

Mac Specific Features

o command which opens the specified bookmark in Finder
t command which opens the specified bookmark in a new Terminal tab.

y web          # opens ~/home/projects/www/  in a new tab
cd javascript
y              # opens ~/home/projects/www/javascript in a new tab

o              # opens ~/home/projects/www/javascript in Finder

Install

git clone git://github.com/Bilalh/shellmarks.git
make install
source ~/.local/bin/shellmarks.sh from within your ~.bash_profile or ~/.bashrc

download https://raw.githubusercontent.com/Bilalh/shellmarks/master/shellmarks.sh and source it from within your ~.bash_profile or ~/.bashrc

More Information

See the project page for information.

Useful sed commands

bilalshussain@gmail.com (Bilal Syed Hussain) — Sun, 09 Oct 2011 17:20:59 +0000

Delete nth line inplace

sed -i .tmp '<n>d' <filename>

Get the nth line

sed '<n>q;d' <filename>

Delete the first 10 lines of a file

sed '1,10d'

Delete lines matching pattern

 sed '/pattern/d'