9.7 Rounding Operations

The functions ffloor, fceiling, fround and ftruncate take a floating point argument and return a floating point result whose value is a nearby integer. ffloor returns the nearest integer below; fceiling, the nearest integer above; ftruncate, the nearest integer in the direction towards zero; fround, the nearest integer.

Function: ffloor number

This function rounds number to the next lower integral value, and returns that value as a floating point number.

Function: fceiling number

This function rounds number to the next higher integral value, and returns that value as a floating point number.

Function: ftruncate number

This function rounds number towards zero to an integral value, and returns that value as a floating point number.

Function: fround number

This function rounds number to the nearest integral value, and returns that value as a floating point number.