floating point to standard out

[Allan Pincus]

How do I get standard out from a script to report decimals?

For example:

(( p = 10 / 3 ))
echo $p
3

Not:

3.333333333333

I can't seem to find a good reference for formatting.

I don't ever have this problem using Perl, or some other language, just a silly shell script I'm trying to create to compute some usage ratios.

Thanks!

[James R. Ferguson · Accepted solution]

Hi Allan:

One way is with 'bc':

# X=1;Y=8;echo "scale=3\n $X/$Y"|bc

Regards!

...JRF...

[Anil C. Sedha]

There you go.. JRF has just resolved your issue.

Regards,
Anil

[Allan Pincus]

Thanks!!!!

I've been doing this stuff for almost 8 years, and I still learn new things everyday!!

- Allan

[James R. Ferguson]

Hi Allan:

...and don't forget 'awk':

# X=1;Y=8;echo "$X $Y"|awk '{printf "%.4f\n",$1/$2}'

Regards!

...JRF...

[John Poff]

Hi,

Here is a way using awk. With a script named divider.awk:

{
result = ($1 / $2)
}
END {
printf("result: %12.6f\n", result);
}


You can then do something like this:

echo "10 3" | awk -f divider.awk
result: 3.333333


It isn't pretty, but it is another way to do it. Plus, you can manipulate the output of your numbers with printf.

JP