math.copysign Method (Double, Double)

mathcopysign Method (Double, Double)

Copies the sign of number2 to number1.

Namespace: C
Assembly: C.math (in C.math.dll) Version: 1.0.0.0 (1.0.0.0)

Syntax

public static double copysign(
	double number1,
	double number2
)

Public Shared Function copysign ( 
	number1 As Double,
	number2 As Double
) As Double

public:
static double copysign(
	double number1, 
	double number2
)

static member copysign : 
        number1 : float * 
        number2 : float -> float

Parameters

number1: Type: SystemDouble
A floating-point number.
number2: Type: SystemDouble
A floating-point number.

Return Value

Type: Double
The floating-point number whose absolute value is that of number1 with the sign of number2.

Remarks

copysign(Double, Double) is the only portable way to manipulate the sign of a NaN value (to examine the sign of a NaN, signbit(Double) may also be used).

See copysign in the C standard documentation.

Examples

C++

Copy

Assert.IsTrue(math.copysign(0D, -0D) == -0D);
Assert.IsTrue(math.copysign(0D, -4D) == -0D);
Assert.IsTrue(math.copysign(2D, -0D) == -2D);
Assert.IsTrue(math.copysign(-2D, 0D) == 2D);
Assert.IsTrue(math.copysign(System.Double.PositiveInfinity, -2D) == System.Double.NegativeInfinity);
Assert.IsTrue(math.copysign(2D, System.Double.NegativeInfinity) == -2D);

Assert.IsTrue(math.copysign(0D, -0D) = -0D);
Assert.IsTrue(math.copysign(0D, -4D) = -0D);
Assert.IsTrue(math.copysign(2D, -0D) = -2D);
Assert.IsTrue(math.copysign(-2D, 0D) = 2D);
Assert.IsTrue(math.copysign(System.Double.PositiveInfinity, -2D) = System.Double.NegativeInfinity);
Assert.IsTrue(math.copysign(2D, System.Double.NegativeInfinity) = -2D);

Reference

math Class

copysign Overload

C Namespace