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isnumber [2006/08/01 03:45] (current)
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 +# $EPIC: isnumber.txt,​v 1.2 2006/08/01 03:40:36 sthalik Exp $
 +======Synopsis:​======
 +$__isnumber__(<​text>​) \\ 
 +$__isnumber__(b<​base-num>​ <​text>​) \\
 +$__isnumber__(<​text>​ b<​base-num>​)
 +
 +======Technical:​======
 +   * The <​base-num>​ argument may either be the first or second word, but in either case must be prefixed with the literal '​b'​ character.
 +   * The <​text>​ argument may either be the first or second word, but in either case must NOT be prefixed with the literal '​b'​ character.
 +   * If the <​base-num>​ argument is not specified, the default value is 0.
 +   * If <​base-num>​ is 0, the number base is auto-detected.
 +   * <​text>​ is taken to be a string containing an integer value, a decimal point ('​.'​ -- sorry), and another integer value; comprised of digits which are legal in the indicated base.
 +   * If a decimal point is used and the <​base-num>​ is 0, then the integer value after the decimal point must be in base 10 and will not be auto-detected.
 +   * The return value is 1 if <​text>​ is a valid number in the indicated base, and 0 if <​text>​ is not a valid number in the indicated base.
 +
 +======Practical:​======
 +Wow.  That's complicated. ​ This function (believe it or not) just tells
 +you whether or not <​text>​ is a number. ​ You can specify a number base
 +(such as b8, or b16) to see if <​text>​ is a number in a base other than 
 +base 10.  This is neccesary if you want to octal or hexidecmial numbers
 +for validity.
 +
 +======Returns:​======
 +1 if <​text>​ is a valid number of base <​base-num>;​ 0 if not.
 +
 +======Examples:​======
 +<​file>​
 +$isnumber(10) ​            ​returns 1
 +$isnumber(hello) ​         returns 0
 +$isnumber(0xdeadbeef) ​    ​returns 1  (all hex digits!)
 +$isnumber(b8 0xdeadbeef) ​ returns 0  (not an octal number!)
 +$isnumber(b8 07f932) ​     returns 0  (9 is not an octal digit!)
 +$isnumber(3.4) ​           returns 1
 +$isnumber(b16 a.f)        returns 1
 +$isnumber(a.f) ​           returns 0  (hex digits invalid without 0x)
 +$isnumber(0xa.0) ​         returns 1
 +$isnumber(b16 a.f)        returns 1  (hex digits valid with b16)
 +</​file>​
  
isnumber.txt ยท Last modified: 2006/08/01 03:45 (external edit)