How to find square root of a number?

[colau]

Hi,
How to find square root of a number in bash shell?
Is there any built-in sqrt function?

[kaibob]

I don't know of any built-in square root function. I've just started to learn the bc utility. It will find the square root of a number as follows:


calc=$(echo "sqrt ( 10 )" | bc -l) ; echo $calc

Change the number 10 to whatever is applicable.

[colau]

I don't know of any built-in square root function. I've just started to learn the bc utility. It will find the square root of a number as follows:


calc=$(echo "sqrt ( 10 )" | bc -l) ; echo $calc

Change the number 10 to whatever is applicable.

What are the other mathematical functions available in bash shell(like "sqrt")?


floor
ceil
pow

[soltanis]

They're not available through bash, they're available through the bc (1) utility, a command line calculator. Look through its manpage for syntax + examples.

[geirha]

Bash can only do integer arithmetics, not floating point, so you have to rely on an external program to do those types of calculations.


$ echo $((2+2))
4
$ echo $((5/2))
2

[colau]

Bash can only do integer arithmetics, not floating point, so you have to rely on an external program to do those types of calculations.


$ echo $((2+2))
4
$ echo $((5/2))
2

What are those external programs?One is bc.

[Arndt]

What are those external programs?One is bc.

For example:


$ python -c 'import math; print math.sqrt(3)'
1.73205080757
$ perl -e 'print sqrt(3), "\n"'
1.73205080756888

[credobyte]

http://abs-guide.awardspace.com/mathc.php - give it a try :)

[djbushido]

You could write simple C/C++ programs to "import <math.h>" and then perform a simple function and exit - like cos, sqrt, etc. But I like the idea of a python shell a bit more, personally.