## Performing calculations in unix

Posted by John Hallas on August 31, 2009

Normally if I working on a database and want perform simple calculations I use the Oracle database rather than starting up the windows calculator.

select 6*1024*1024 from dual; 6*1024*1024 ----------- 6291456

However I recently found out a method of using unix itself (I am sure there are many more options other than this one but I find this quite easy)

man bc gives

bc is an interactive processor for a language that resembles C but provides unlimited-precision arithmetic. It takes input from any files given, then reads the standard input.

In usage

/home/oracle $bc 6*1024*1024 6291456 quitArithmetic operators are shown in the normal manner + - * / % ^ and there are lots of functions available such as sine, cosine and log, although I would be likely to use a calculator if I wanted to use these.

## danirey said

Thanks for sharing. When using Linux with KDE I prefer to do calculations in the “run command” window (works only with KDE < Version 4)

You can usually open the "run command" dialog with Alt+F2, or in the KDE Menu. If you want to proceed with results 0.2342 Otherwise it’s not recognized as a number.

## pgreenwood said

I go to python for quick calculations.

## John Hallas said

Thanks Patrick, there are lots of ways of doing calculations using shell, perl, python bit I found bc nice and easy (and there is an alternative dc which looks very simple as well)

## lbolla said

I strongly recommend you:

$> bc -l

otherwise 1/2 = 0, instead of 0.5!

L

## John Hallas said

Just checked that out. Good call.

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