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Compute running average for a column of numbers
This is an on-line algorithm for calculating the mean value for numbers in a column. Also known as "running average" or "moving average".

permanently let grep colorize its output
This will create a permanent alias to colorize the search pattern in your grep output

Use tagged vlans
Great for sysadmins! Don't forget to pass the vlan to your port in a manageable switch. After vconfig, you should use $sudo ifconfig eth0.[VID] up Now the interface is up, you can use dhclient or ifconfig again to get an ip address.

find an unused unprivileged TCP port
perl-less way

SoX recording audio and trimming silence
Records audio from your mic in FLAC (Free Lossless Audio Codec) format, starts only after it detects at least 0.1 seconds of noise and stops after 1 second of silence. You can adjust the percent values (sensitivity) to best fit your microphone and voice (0.1% if you have a great quality mic, higher if you don't, 0% does not trim anything). Useful for speech recognition in conjunction with my previous command titled 'Google voice recognition "API"' (http://www.commandlinefu.com/commands/view/8043/google-voice-recognition-api).

Convert CSV to JSON
Replace 'csv_file.csv' with your filename.

Sniff ONLY POP3 authentication by intercepting the USER command
dsniff is general purpose password sniffer, it handles *lots* of different protocols, but it also handles tcp-style expressions for limiting analyzed traffic - so I can limit it to work on pop3 only.

subtraction between lines
It's allways strange for me to see sed and awk in the same command line if you can avoid it

Convert Shell Text to Upper/Lower Case

Removing Prefix from File name
Removing Course name prefix added


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