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May 19, 2015 - A Look At The New Commandlinefu
I've put together a short writeup on what kind of newness you can expect from the next iteration of clfu. Check it out here.
March 2, 2015 - New Management
I'm Jon, I'll be maintaining and improving clfu. Thanks to David for building such a great resource!

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Psst. Open beta.

Wow, didn't really expect you to read this far down. The latest iteration of the site is in open beta. It's a gentle open beta-- not in prime-time just yet. It's being hosted over at UpGuard (link) and you are more than welcome to give it a shot. Couple things:

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Your feedback is appreciated via the form on the beta page. Thanks! -Jon & CLFU Team

Using numsum to sum a column of numbers.

Terminal - Using numsum to sum a column of numbers.
echo $(( $( cat count.txt | tr "\n" "+" | xargs -I{} echo {} 0 ) ))
2010-01-27 10:02:30
User: glaudiston
Functions: cat echo tr xargs
Using numsum to sum a column of numbers.

if you, like me, do not have the numsum, this way can do the same.


There are 2 alternatives - vote for the best!

Terminal - Alternatives
cat count.txt | awk '{ sum+=$1} END {print sum}'
2009-03-16 00:22:13
User: duxklr
Functions: awk cat
Tags: awk

Takes a input file (count.txt) that looks like:






It will add/sum the first column of numbers.

numsum count.txt
2010-01-26 21:53:18
User: deltaray

numsum is part of of the num-utils package, which is available in some Linux distros and can also be downloaded at http://suso.suso.org/xulu/Num-utils. It contains about 10 different programs for dealing with numbers from the command line.

Obviously you can do a lot of things that the num-utils programs do in awk, sed, bash, perl scripts, but num-utils are there so that you don't have to remember the syntax for more complex operations and can just think: compute the sum, average, boundary numbers, etc.

Know a better way?

If you can do better, submit your command here.

What others think

xargs is mega redundant.

echo $(($(seq 1000000 | tr "\n" "+"; echo 0)))
Comment by pixelbeat 352 weeks and 1 day ago

Your point of view

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