gmp_lib.mpn_mul_1 Method

GMP Native Interface for .NET

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gmp_libmpn_mul_1 Method
Multiply {s1p, n} by s2limb, and write the n least significant limbs of the product to rp.

Namespace:  Math.Gmp.Native
Assembly:  Math.Gmp.Native (in Math.Gmp.Native.dll) Version: 1.0.0.0 (1.0.0.0)
Syntax
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public static mp_limb_t mpn_mul_1(
	mp_ptr rp,
	mp_ptr s1p,
	mp_size_t n,
	mp_limb_t s2limb
)
Public Shared Function mpn_mul_1 ( 
	rp As mp_ptr,
	s1p As mp_ptr,
	n As mp_size_t,
	s2limb As mp_limb_t
) As mp_limb_t
public:
static mp_limb_t mpn_mul_1(
	mp_ptr^ rp, 
	mp_ptr^ s1p, 
	mp_size_t n, 
	mp_limb_t s2limb
)
static member mpn_mul_1 : 
        rp : mp_ptr * 
        s1p : mp_ptr * 
        n : mp_size_t * 
        s2limb : mp_limb_t -> mp_limb_t

Parameters

rp
Type: Math.Gmp.Nativemp_ptr
The result integer.
s1p
Type: Math.Gmp.Nativemp_ptr
The first operand integer.
n
Type: Math.Gmp.Nativemp_size_t
The number of limbs of s1p.
s2limb
Type: Math.Gmp.Nativemp_limb_t
The second operand integer.

Return Value

Type: mp_limb_t
Return the most significant limb of the product.
Remarks

{s1p, n} and {rp, n} are allowed to overlap provided rp ≤ s1p.

This is a low-level function that is a building block for general multiplication as well as other operations in GMP. It is written in assembly for most CPUs.

Don’t call this function if s2limb is a power of 2; use mpn_lshift with a count equal to the logarithm of s2limb instead, for optimal speed.

Examples
Copy
// Create multi-precision operands, and expected result.
mp_ptr s1p = new mp_ptr(new uint[] { 0xffffffff, 0xffffffff });
mp_ptr rp = new mp_ptr(new uint[2]);
mp_ptr result = new mp_ptr(new uint[] { 0xfffffffe, 0xffffffff });

// Set rp = s1 * 2.
mp_limb_t carry = gmp_lib.mpn_mul_1(rp, s1p, s1p.Size, 2);

// Assert result of operation.
Assert.IsTrue(carry == 1);
Assert.IsTrue(rp.SequenceEqual(result));

// Release unmanaged memory.
gmp_lib.free(rp, s1p, result);
' Create multi-precision operands, and expected result.
Dim s1p As New mp_ptr(New UInteger() { &HffffffffUI, &HffffffffUI})
Dim rp As New mp_ptr(New UInteger(1) { })
Dim result As New mp_ptr(New UInteger() { &HfffffffeUI, &HffffffffUI})

' Set rp = s1 * 2.
Dim carry As mp_limb_t = gmp_lib.mpn_mul_1(rp, s1p, s1p.Size, 2)

' Assert result of operation.
Assert.IsTrue(carry = 1)
Assert.IsTrue(rp.SequenceEqual(result))

' Release unmanaged memory.
gmp_lib.free(rp, s1p, result)

No code example is currently available or this language may not be supported.

No code example is currently available or this language may not be supported.

See Also
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