#!/bin/perl
#+
# is_float -- check whether the argument is floating point number
#
# Purpose:
#	Check whether the arguments are valid flaoting point numbers
#	by doing a pattern match.
#
# Usage:
#	is_float [arg1 arg2 ... argN]
# 
# Arguments:
#	arg1, etc:	strings to be evaluated as possible numbers
# 
# Output:
#	Each valid float is printed on STDOUT
# 
# Restrictions
#	A leading "+" will invalidate the string; e.g., "+1.00" is not
#	considered a valid number.
# 
# Exit values:
#	 0 = normal completion; all values are floats
#	 1 = non-floats detected
#
# Type:
#	Perl5 script
#
# Example:
#	1) check whether a variable is a floating point value:
#		set a = 1.234
#		is_float $a
#		echo $status	( returns 0 ==> good)
#-
# Modification history:
#	Date unknown	RWG	Original version
#	2000-Jul-05	GDW	Added documentation
#-----------------------------------------------------------------------
$status = 0;
foreach $arg ( @ARGV ) {
  $_ = $arg ; 
  if ( /^-?(?:\d+(?:\.\d*)?|\.\d+)$/ ) { print ; print "\n"} else { $status=1}
}
exit $status;