How to Compare Floating point / real numbers

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# 1  
Old 09-18-2007
How to Compare Floating point / real numbers


Can you please guide me, to compare the floating point numbers.


If [ $value1 > $value2 ]

echo "value1 is grater "


This code is not working properly when i excuted with floating values or real numbers
# 2  
Old 09-18-2007
With zsh:

% [[ 0.3 -gt 0.1 ]]&& echo OK||echo KO
% [[ 0.3 -lt 0.1 ]]&& echo OK||echo KO

# 3  
Old 09-18-2007
Hammer & Screwdriver Try This one


I hope you can do it by awk. For me it is working fine
# x=3.1; y=3.2; echo "$x $y" | awk '{if ($1 > $2) print $1; else print $2}'

I'm sure you can adapt it to your script

# 4  
Old 09-18-2007
You can do it by using bc

You also can achieve that by using bc

Result=`echo "$Value1 > $Value2" | bc`

if [ $Result -eq 1 ]
echo "value1 is greater"
# 5  
Old 09-18-2007
Hi Virmin,

After excuting your code. i am getting a syntax error .

echo "Enter value1"
read value1
echo "Enter value2"
read value2

Result=`echo "$Value1 > $Value2" | bc `

if [ $Result -eq 1 ]
echo "$value1 is greater"

syntax error on line 1, teletype
# 6  
Old 09-18-2007
You are reading value1 and echoing Value1. (And ditto for value2.) value1 and Value1 are 2 different variables.
# 7  
Old 09-18-2007


if [ "$(echo "if (${a} > ${b}) 1" | bc)" -eq 1 ] ; then
   echo ">"
   echo "<"

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