php man page for intval

INTVAL(3)								 1								 INTVAL(3)

intval - Get the integer value of a variable

SYNOPSIS
       int intval (mixed  $var, [int  $base = 10])

DESCRIPTION
	Returns  the integer value of $var, using the specified $base for the conversion (the default is base 10). intval(3) should not be used on
       objects, as doing so will emit an E_NOTICE level error and return 1.

PARAMETERS
	      o $var
		- The scalar value being converted to an integer

	      o $base
		- The base for the conversion

	      Note

		      If $base is 0, the base used is determined by the format of $var:

			    o if string includes a "0x" (or "0X") prefix, the base is taken as 16 (hex); otherwise,

			    o if string starts with "0", the base is taken as 8 (octal); otherwise,

			    o the base is taken as 10 (decimal).

RETURN VALUES
	The integer value of $var on success, or 0 on failure. Empty arrays return 0, non-empty arrays return 1.

	The maximum value depends on the system. 32 bit systems have a maximum signed integer range of -2147483648 to 2147483647. So  for  example
       on   such   a  system,  intval('1000000000000')	will  return  2147483647.  The	maximum  signed  integer  value  for  64  bit  systems	is
       9223372036854775807.

	Strings will most likely return 0 although this depends on the leftmost characters of the string. The  common  rules  of  integer  casting
       apply.

EXAMPLES
       Example #1

	      intval(3) examples

	       The following examples are based on a 32 bit system.

	      <?php
	      echo intval(42);			    // 42
	      echo intval(4.2); 		    // 4
	      echo intval('42');		    // 42
	      echo intval('+42');		    // 42
	      echo intval('-42');		    // -42
	      echo intval(042); 		    // 34
	      echo intval('042');		    // 42
	      echo intval(1e10);		    // 1410065408
	      echo intval('1e10');		    // 1
	      echo intval(0x1A);		    // 26
	      echo intval(42000000);		    // 42000000
	      echo intval(420000000000000000000);   // 0
	      echo intval('420000000000000000000'); // 2147483647
	      echo intval(42, 8);		    // 42
	      echo intval('42', 8);		    // 34
	      echo intval(array());		    // 0
	      echo intval(array('foo', 'bar'));     // 1
	      ?>

NOTES
       Note

	       The $base parameter has no effect unless the $var parameter is a string.

CHANGELOG
       +--------+---------------------------------------------------+
       |Version |						    |
       |	|						    |
       |	|		     Description		    |
       |	|						    |
       +--------+---------------------------------------------------+
       | 5.1.0	|						    |
       |	|						    |
       |	|  Throws E_NOTICE and returns 1, when an object is |
       |	| passed to $var.				    |
       |	|						    |
       +--------+---------------------------------------------------+
SEE ALSO
       boolval(3), floatval(3), strval(3), settype(3), is_numeric(3), Type juggling, BCMath Arbitrary Precision Mathematics Functions.

PHP Documentation Group 														 INTVAL(3)