shell script

[Jeff Hoevenaar_1]

I am trying to get a decimal output from the following.


let a=50/100
echo $a

output is 0
how do I get a 0.50 output?

[Paul Hite_2]

Try:

a=`echo "scale=2 ; 50 / 100" | bc`
echo $a

[Klaus Frank]

Hi

try formated output with

printf "%5.2f" $a

see man printf for detailed information

best regards
Klaus Frank

[Brian M. Fisher]

Hoovey,

Try the following:
X=$(print|awk '{printf("%.2fn",50/100)}')

This may look ugly, but the awk command is capable of processing floating-point numbers.

Details of the command:
$() - execute the shell commands within
awk - awk command
print - pass awk blank line
printf - formatted print command
%.2f - real number 2 places past decimal
n - newline

Brian
<*(((>< er

[Emmanuel Eyer]

Shell makes only integer calculation. Use bc if you need floating point (see previous answer) is a good idea, since bc is quite universal. However, there might be situations where you do not want to (or you cannot) rely on external programs.

It is possible, though a bit complicated, to do it all in Shell (Posix/Korn, but may work in Bourne too) using a function. I wrote such a function (called fdiv), put in the attachment. For example:

$ fdiv 3 7 3
0.428

(the 3rd parameter is the number of digits).

Hope it helps,
Emmanuel

[curt larson]

you could do this

#! /usr/dt/bin/dtksh

float a # float is usually aliased to typeset -E

(( a = 50/100 ))
printf "%fn" $a

[curt larson]

looks like the back slash didn't show up in the printf format statement.

printf "fn" $a

of course the printf supports the usual C syntax of:
%[flags][field_width][precision][base]conversion

[curt larson]

I dont' why the percent of the backslash isn't showing up. So I'll put the format into a word format and hope you can understand that better;

printf "(percent)f(backslash)n" $a

[CHRIS_ANORUO]

Curt, use (double slash) //
It is a thing with the forum postin, for front slash to appear, you have to make it double too.

[CHRIS_ANORUO]

bc -l will give you decimal points in you calculations.

[George A Bodnar]

Do the following to vary your formula and get results in decimal:

# Set scale = # of decimal places you want
NUMBER="10/5" # Your formula
ANSWER=`bc -l <<-EOF
scale = 2
${NUMBER}
EOF`

This should work for you, but the value in ANSWER is text, not number since shell can
only handle integer values.