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Top Forums Shell Programming and Scripting Check if a variable has a value assigned? Post 302312859 by cfajohnson on Sunday 3rd of May 2009 11:48:32 PM
Old 05-04-2009

Code:
if [ -z "${var+X}" ]
then
  echo var is unset
elif [ -z "$var" ]
then
  echo var is set but empty
else
  echo "The value of \$var is $var"
fi

 

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FLOATVAL(3)								 1							       FLOATVAL(3)

floatval - Get float value of a variable

SYNOPSIS
float floatval (mixed $var) DESCRIPTION
Gets the float value of $var. PARAMETERS
o $var - May be any scalar type. floatval(3) should not be used on objects, as doing so will emit an E_NOTICE level error and return 1. RETURN VALUES
The float value of the given variable. Empty arrays return 0, non-empty arrays return 1. Strings will most likely return 0 although this depends on the leftmost characters of the string. The common rules of float casting apply. EXAMPLES
Example #1 floatval(3) Example <?php $var = '122.34343The'; $float_value_of_var = floatval($var); echo $float_value_of_var; // 122.34343 ?> Example #2 floatval(3) non-numeric leftmost characters Example <?php $var = 'The122.34343'; $float_value_of_var = floatval($var); echo $float_value_of_var; // 0 ?> SEE ALSO
boolval(3), intval(3), strval(3), settype(3), Type juggling. PHP Documentation Group FLOATVAL(3)
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