Inside Macintosh: PowerPC Numerics / Part 2 - The PowerPC Numerics C Implementation

Chapter 9 - Conversion Functions

Converting Floating-Point to Integer Formats

In C, the default method of converting floating-point numbers to integers is to simply discard the fractional part (truncate). MathLib provides two functions that convert floating-point numbers to integers using methods other than the default C method and that return the integers in integer types.

$rinttol(x)$	Returns the nearest integer to x in the current rounding direction as an integer type.
$roundtol(x)$	Adds 1/2 to the magnitude of x, chops to an integer, and returns the value as an integer type.