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Salathe · 11-29-2008, 02:52 PM

The number 042 is an octal number (base 8) rather than a 'normal' decimal number (base 10). It's the octal 42 which can be explained below:

Octal

Code:

32 16  8  1
-  -   4  2

To work out the decimal value, multiply the header line by the digit line and sum those values. 8*4 + 1*2 which gives 34.

Compare this to decimal numbers

Code:

1000 100 10  1
-    -   4   2

Multiplying the values together again: 10*4 + 1*2 which gives 42.

You can also use hexadecimal (base 16) by preceding the number with 0x. For example, all of the following have an integer value of 123.

PHP Code:


			
$num = 123;  // decimal

$num = 0x7B; // hexadecimal

$num = 0173; // octal

More information can be found on the integers PHP manual page.

11-29-2008, 02:52 PM	#2 (permalink)
Salathe Moderateur Join Date: Apr 2007 Posts: 1,393 Thanks: 5	The number `042` is an octal number (base 8) rather than a 'normal' decimal number (base 10). It's the octal `42` which can be explained below: Octal Code: 32 16 8 1 - - 4 2 To work out the decimal value, multiply the header line by the digit line and sum those values. `84 + 12` which gives 34. Compare this to decimal numbers Code: 1000 100 10 1 - - 4 2 Multiplying the values together again: `104 + 12` which gives 42. You can also use hexadecimal (base 16) by preceding the number with `0x`. For example, all of the following have an integer value of 123. PHP Code: `$num = 123; // decimal $num = 0x7B; // hexadecimal $num = 0173; // octal` More information can be found on the integers PHP manual page.