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Comparing Negative Numbers with If/Else

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# 1  
Old 07-20-2011
Comparing Negative Numbers with If/Else
ValA=-29344

if [ "$ValA" -lt "0" ] ; then

echo "NEGATIVE"

else

echo "POSITIVE"

fi


Can someone please tell me how else they would go about doing the above?

When i do it, i get errors such as:

Code:
[: 179: Illegal number: 
[: 179: Illegal number:

Last edited by SkySmart; 07-20-2011 at 01:56 PM..
# 2  
Old 07-20-2011
Code:
[ ValA -lt 0 ] && echo "negative" || echo "positive"

# 3  
Old 07-20-2011
Or using builtin
Code:
((  ValA < 0 ))  && echo "negative" || echo "positive"

# 4  
Old 07-20-2011
thanks guys. i tried the suggestions i've received in this thread so far, but none of them seem to work. Smilie
# 5  
Old 07-20-2011
What's your system? What's your shell? Knowing that will help find an answer that works for you, not just us.
# 6  
Old 07-20-2011
Quote:
Originally Posted by Corona688
What's your system? What's your shell? Knowing that will help find an answer that works for you, not just us.


Linux Redhat and Ubuntu

Shell i'm using = /bin/sh


Thanks
# 7  
Old 07-20-2011
sh is "generic" today. More safety is tell the shell from group ksh, bash, dash. Then you have maybe that shell.
Code:
#!/usr/bin/ksh # or bash or dash

But next will work in any posix shell and bourne shell
Code:
[ "$ValA" -lt 0 ] && echo "negative" || echo "positive"
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