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bash: testing if string is a number

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# 1  
Old 07-19-2006
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.
# 2  
Old 07-19-2006
ok I guess it's an error if it's not numeric.

Why not :

typeset -i x before assigning it?
# 3  
Old 07-19-2006
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 Smilie
# 4  
Old 07-20-2006
If only you had searched the forums.... Smilie

How to check whether a string is number or not
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