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How to Compare Floating point / real numbers

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# 8  
Old 09-18-2007
Computer
Quote:
Originally Posted by padarthy
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 [ $Result -eq 1 ]
then
echo "$value1 is greater"
fi




Error:
-----
syntax error on line 1, teletype
as Perderabo said, unix is case sensitive, so value1 and Value1 are totally different variable.
and you have to make sure $Value1 and $Value2 are legal numbers before you use them, or bc will fail.
# 9  
Old 09-19-2007
I corrected the case sensitive, Still i am getting an error

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

Result=`echo $value1 > $value2 | bc `

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

ouput
-----

bash-2.03$ ./compare
Enter value1
5.6
Enter value2
3.2
./compare[9]: test: argument expected

Please correct this.
# 10  
Old 09-19-2007
Result=`echo $value1 > $value2 | bc `

Here Im seeing one whitespace in the end of above command.

so please remove that whitespace.

Result=`echo $value1 > $value2 | bc`

Thanks
~~Sanjay Tripathi~~
# 11  
Old 09-19-2007
Quote:
Originally Posted by padarthy
echo "Enter value1"
read value1
echo "Enter value2"
read value2

Result=`echo $value1 > $value2 | bc `

if [ $Result -eq 1 ]
then
echo "$value1 is greater"
fi
Change
Code:
if [ $Result -eq 1 ]

to
Code:
if [[ $Result -eq 1 ]]

This will only resolve the error that you are seeing.
# 12  
Old 09-19-2007
Vino, after changing the code..

I am not getting the output .. No errors were display
Last edited by padarthy; 09-19-2007 at 11:11 PM..
# 13  
Old 09-20-2007
Er, the input to bc is incorrect. It will give you an error. Use this:
Code:
echo "Enter value1"
read value1
echo "Enter value2"
read value2

Result=`echo "if($value1 > $value2) 1" | bc `

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

vgersh99 has very similar code in his post... you could have used that as well.
# 14  
Old 09-24-2007
Hi I am getting the error

Here is the output

bash-2.03$ ./file4
Enter value1
4568456
Enter value2
6589546
./file4: [: -eq: unary operator expected


Please correct this code

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

Result=`echo "if($value1 > $value2) 1" | bc `

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