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Checking input for being numeric and integers


 
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# 1  
Old 09-21-2009
Checking input for being numeric and integers

Hi, I'm trying to check to see that the arguments given to my script are both numeric and positive integers. I'm using tcsh. I figured out the positive part, but I am having trouble with the arguments being numeric and integers
I have no idea where to get started with the checking them actually being numbers...could someone point me in the right direction?
As for the integer part, this is currently what I have written:
@ int = 1
if ( $argv[1] % $int != 0 ) then
echo "not an integer"
endif

However, when this is executed, I get the error message of
if: Badly formed number.

Can if statements only take integers? If so, how can I check to see that the given argument is an integer?
# 2  
Old 09-22-2009
I don't know about tcsh, but bash has different comparison operators for numbers and strings. So, by applying an arithmetic comparison, I will receive an error message if the operands are strings.
In code:
[code]
#!/bin/bash

if [ $1 -eq $1 2>/dev/null ]; then
echo Is number
else
echo Is NOT a number
fi

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