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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

Quick command line math

Terminal - Quick command line math
expr 512 \* 7
2009-09-23 19:11:38
User: chuckr
Functions: expr
Quick command line math

expr will give you a quick way to do basic math from the CLI. Make sure you escape things like * and leave a space between operators and digits.


There are 9 alternatives - vote for the best!

Terminal - Alternatives

Know a better way?

If you can do better, submit your command here.

What others think

Doesn't do decimals. Try this Perl command.

perl -le 'print 51.2 * 2'

Comment by billbose 369 weeks and 3 days ago

bc does floating point, large powers and trig functions too



bc -l




Comment by Escher 369 weeks and 3 days ago

the comment above came out wrong

bc <<< 512*7


bc -l <<< 512/7


bc <<< 512^7


Comment by Escher 369 weeks and 3 days ago

if you don't care about decimals then try

echo $((512*7))

you don't need to care about spaces nor escaping anything

Comment by edo 369 weeks and 3 days ago

All good solutions too. But the original wins for fewest number of keystrokes :-)

Also, the bc example above seems wrong.

echo "512*7" | bc

will work.

Comment by chuckr 369 weeks and 3 days ago

the bc examples use bash 'here string' operator, it won't work in other shells, but in bash it's the fewest keystrokes, and more versatile.

Comment by Escher 369 weeks and 2 days ago
bc <<< 512*7

is 12 keystrokes

expr 512 \* 7

is 13 keystrokes

Comment by Escher 369 weeks and 2 days ago

and in fact, it could just be


which is 10 keystrokes.

Comment by Escher 369 weeks and 2 days ago

OK. I wasn't using bash when trying the '

Comment by chuckr 369 weeks and 2 days ago

OK. I wasn't using bash when trying the 'here string' solution so I didn't count its keystrokes. Good solution, if using bash.

Comment by chuckr 369 weeks and 2 days ago

Your point of view

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