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bash: testing if string is a number

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Old Unix and Linux 07-19-2006
eur0dad eur0dad is offline
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bash: testing if string is a number

How do you test if a string is a number?

Trying to do something like this:

x="AS"
if( x is not a number ); then
x=0
fi

Because I want to do number arithmetic with x.
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ok I guess it's an error if it's not numeric.

Why not :

typeset -i x before assigning it?
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Doc_RuNNeR Doc_RuNNeR is offline
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Below I write a code with tow output the first one is to numeric arguments and the second if it isnīt numeric

Code:
#!/bin/bash
if echo $1 | grep "^[0-9]*$">aux
then
  echo "La cadena es un valor numerico."
else
  echo "La cadena no es un valor numerico."
fi
rm aux

Enjoy that, and please correct my english Linux
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If only you had searched the forums.... Linux

How to check whether a string is number or not
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