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mpfr_libmpfr_remquo Method (mpfr_t, Int32, mpfr_t, mpfr_t, mpfr_rnd_t)
Set r to the value of x - n * y, rounded according to the direction rnd, where n is the integer quotient of x divided by y, rounded to the nearest integer (ties rounded to even).

Namespace:  Math.Mpfr.Native
Assembly:  Math.Mpfr.Native (in Math.Mpfr.Native.dll) Version: 1.0.0.0 (1.0.0.0)
Syntax
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public static int mpfr_remquo(
	mpfr_t r,
	ref int q,
	mpfr_t x,
	mpfr_t y,
	mpfr_rnd_t rnd
)

Parameters

r
Type: Math.Mpfr.Nativempfr_t
The result remainder floating-point number.
q
Type: SystemInt32
Low significant bits of quotient.
x
Type: Math.Mpfr.Nativempfr_t
The first operand floating-point number.
y
Type: Math.Mpfr.Nativempfr_t
The second operand floating-point number.
rnd
Type: Math.Mpfr.Nativempfr_rnd_t
The rounding direction.

Return Value

Type: Int32
The return value is the ternary value corresponding to r. See GNU MPFR - Rounding Modes for details.
Remarks

Special values are handled as described in Section F.9.7.1 of the ISO C99 standard: If x is infinite or y is zero, r is NaN. If y is infinite and x is finite, r is x rounded to the precision of r. If r is zero, it has the sign of x.

Additionally, O:Math.Mpfr.Native.mpfr_lib.mpfr_remquo stores the low significant bits from the quotient n in q (more precisely the number of bits in a long minus one), with the sign of x divided by y (except if those low bits are all zero, in which case zero is returned). Note that x may be so large in magnitude relative to y that an exact representation of the quotient is not practical. The mpfr_remainder and O:Math.Mpfr.Native.mpfr_lib.mpfr_remquo functions are useful for additive argument reduction.

Examples
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// Create, initialize, and set a new floating-point number x to 100.
mpfr_t x = new mpfr_t();
mpfr_lib.mpfr_init2(x, 64U);
Assert.IsTrue(mpfr_lib.mpfr_set_si(x, 100, mpfr_rnd_t.MPFR_RNDN) == 0);

// Create, initialize, and set a new floating-point number y to 7.
mpfr_t y = new mpfr_t();
mpfr_lib.mpfr_init2(y, 64U);
Assert.IsTrue(mpfr_lib.mpfr_set_si(y, 7, mpfr_rnd_t.MPFR_RNDN) == 0);

// Create and initialize a new floating-point number r.
mpfr_t r = new mpfr_t();
mpfr_lib.mpfr_init2(r, 64U);

// Set r = x - n * y where n = trunc(x / y).
int q = 0;
Assert.IsTrue(mpfr_lib.mpfr_remquo(r, ref q, x, y, mpfr_rnd_t.MPFR_RNDN) == 0);

// Assert the value of z and q.
Assert.IsTrue(r.ToString() == "0.200000000000000000000e1" && q == 14);

// Release unmanaged memory allocated for r, x, and y.
mpfr_lib.mpfr_clears(r, x, y, null);
See Also