Comparison of floating point values in shell

Hi Everyone ,

Need a simple code here , I Have a number in a variable say $a=145.67 . This value changes everytime loop begins .

I need to print a specific message as shown below when the above variable lies in a specific range i.e.

1.if $a lies within 100 and 200 , it should display message1

2.if $a lies within 200 and 300 , it should display message2

3. if $a lies within 300 and 400 , it should display message 3 .

I Have a code which is not working :

if [$a -ge 100 ] && [$a -lt 200 ]
then
echo "message1"

elseif [$a -ge 200] && [$a -lt 300 ]
then
echo "message2"

elseif [$a -ge 300] && [$a -lt 400 ]
then 
echo "message3"
fi

Note :
variable is a floating number .

would appreciate if someone could fix this or provide a better simple code .

One of the Error am getting :

a.ksh[5]: if[16783934.78:  not found
+ echo 16783934.78
+ 1> mes.txt
a.ksh[7]: syntax error at line 8 : `else' unexpected

As a start, put a blank between each square bracket and the variables. Try elif instead of elseif .

if [ $a -ge 100 ] && [ $a -lt 200 ]
then
     echo "message1"
elif [ $a -ge 200 ] && [ $a -lt 300 ]
then
     echo "message2"
elseif [ $a -ge 300 ] && [ $a -lt 400 ]
then 
     echo "message3"
fi

Indention of code is also a good thing to do.

Oh and forgot to point out, should use double square brackets together with >=, <= .... to be able to compare floating point values.

In recent versions of ksh, you can compare integer and floating point values with both [ expr ] and [[ expr ]] , but there are no >= or <= operators and < and > in [[ expr ]] comparisons are for comparing string values, not arithmetic values.

The suggested changes zaxxon proposed in the code tags should work fine when using a ksh version newer than 1988, but keep the -ge and -lt rather than trying to use >= and < for arithmetic comparisons.