quo_mod.h File Reference

Quotient and modulus prototypes. More...

This graph shows which files directly or indirectly include this file:

Go to the source code of this file.

Data Structures
struct	quo_mod
	Quotient and remainder in integer space. More...

Functions
struct quo_mod	quo_mod (int x, int y)
	Compute the integer quotient and modulus.

Detailed Description

Quotient and modulus prototypes.

Header file for quotient and modulus function implementations.

Copyright

2025, Roy Ratcliffe, Northumberland, United Kingdom

Definition in file quo_mod.h.

Function Documentation

quo_mod()

struct quo_mod quo_mod	(	int	x,
		int	y
	)

Compute the integer quotient and modulus.

Performs an integer modulo operation. Then subtracts the modulus from the numerator and applies an integer division in order to compute the quotient.

The following invariant proves true: the numerator matches the denominator multiplied by the quotient plus the modulus.

struct quo_mod qm = quo_mod(x, y);
x == (y * qm.quo + qm.mod);

Parameters

x	Numerator integer.
y	Denominator integer. Must not be zero.

Returns

quo_mod structure comprising the quotient and modulus.

Remarks

Like Lua's modulo operator, this function ensures that the modulus is always non-negative when the denominator is positive, and always non-positive when the denominator is negative.

Note

The quo_mod identifier exists in structure namespace as well as function namespace.

Warning

Throws a division-by-zero error if the denominator y is zero.

Definition at line 12 of file quo_mod.c.