Golang 中的数学包

Go 语言为基本常量和数学函数提供内置支持，以在 math 包的帮助下对数字执行运算。

Function	Description
Abs	This function is used to return the absolute value of the specified number.
Acos	This function returns the arccosine, in radians of the specified number.
Acosh	This function returns the inverse hyperbolic cosine of the specified number.
Asin	This function returns the arcsine, in radians of the specified number.
Asinh	This function returns the inverse hyperbolic sine of the specified number.
Atan	This function returns the arctangent, in radians of the specified number.
Atan2	This function returns the arc tangent of a/b, using the signs of the two to determine the quadrant of the return value.
Atanh	This function returns the inverse hyperbolic tangent of the specified number.
Cbrt	This function returns the cube root of the specified number.
Ceil	This function returns the least integer value greater than or equal to the specified number.
Copysign	This function returns a value with the magnitude of a and the sign of b.
Cos	This function returns the cosine of the radian argument of the specified number.
Cosh	This function returns the hyperbolic cosine of the specified number.
Dim	This function returns the maximum of a – b or 0.
Erf	This function returns the error function of the specified number.
Erfc	This function returns the complementary error function of the specified number.
Erfcinv	This function returns the inverse of Erfc(y).
Erfinv	This function returns the inverse error function of the specified number.
Exp	This function returns e**y, the base-e exponential of the specified number.
Exp2	This function returns 2**y, the base-2 exponential of the specified number.
Expm1	This function returns e**y – 1, the base-e exponential of y minus 1.
FMA	This function returns a * b + c, computed with only one rounding.
Float32bits	This function returns the IEEE 754 binary representation of x, with the sign bit of x and the result in the same bit position.
Float32frombits	This function returns the floating-point number corresponding to the IEEE 754 binary representation x, with the sign bit of x and the result in the same bit position.
Float64bits	This function returns the IEEE 754 binary representation of x, with the sign bit of x and the result in the same bit position, and Float64bits(Float64frombits(y)) == y.
Float64frombits	This function returns the floating-point number corresponding to the IEEE 754 binary representation x, with the sign bit of x and the result in the same bit position.
Floor	This function returns the greatest integer value less than or equal to the specified number.
Frexp	This function is used to breaks t into a normalized fraction and an integral power of two and returns frac and exp satisfying t == frac × 2**exp, with the absolute value of frac in the interval [½, 1).
Gamma	This function returns the Gamma function of the specified number.
Hypot	This function returns Sqrt(a*a + b*b), taking care to avoid unnecessary overflow and underflow.
Ilogb	This function returns the binary exponent of the specified number as an integer.
Inf	This function returns positive infinity if sign >= 0, negative infinity if sign < 0.
IsInf	This function reports whether t is an infinity, according to sign.
IsNaN	This function reports whether t is an IEEE 754 “not-a-number” value.
J0	This function returns the order-zero Bessel function of the first kind.
J1	This function returns the order-one Bessel function of the first kind.
Jn	This function returns the order-n Bessel function of the first kind.
Ldexp	This function is the inverse of Frexp.
Lgamma	This function returns the natural logarithm and sign (-1 or +1) of Gamma(y).
Log	This function returns the natural logarithm of the specified number.
Log10	This function returns the decimal logarithm of the specified number.
Log1p	This function returns the natural logarithm of 1 plus its argument of the specified number.
Log2	This function is used to return the binary logarithm of the specified number.
Logb	This function returns the binary exponent of the specified number.
Max	This function returns the larger of a or b.
Min	This function returns the smaller of a or b.
Mod	This function returns the floating-point remainder of a/b
Modf	This function returns integer and fractional floating-point numbers that sum to f.
NaN	This function returns an IEEE 754 “not-a-number” value.
Nextafter	This function is used to return the next representable float64 value after a towards b.
Nextafter32	This function returns the next representable float32 value after a towards b.
Pow	This function returns a**b, the base-a exponential of b.
Pow10	This function returns 10**m, the base-10 exponential of m.
Remainder	This function returns the IEEE 754 floating-point remainder of a/b.
Round	This function is used to return the nearest integer, rounding half away from zero.
RoundToEven	This function returns the nearest integer, rounding ties to even.
Signbit	This function reports whether x is negative or negative zero.
Sin	This function returns the sine of the radian argument y.
Sincos	This function returns Sin(x), Cos(x).
Sinh	This function returns the hyperbolic sine of the specified number.
Sqrt	This function returns the square root of the specified number.
Tan	This function returns the tangent of the radian argument y.
Tanh	This function returns the hyperbolic tangent of the specified number.
Trunc	This function returns the integer value of the specified number.
Y0	This function returns the order-zero Bessel function of the second kind.
Y1	This function returns the order-one Bessel function of the second kind.
Yn	This function returns the order-n Bessel function of the second kind.

示例 1：

// Golang program to illustrate how to 
// find the IEEE 754 binary representation 
package main 
   
import ( 
    "fmt"
    "math"
) 
   
// Main function 
func main() { 
   
    // Finding IEEE 754 binary 
    // representation of the 
    // given numbers 
    // Using Float64bits() function 
    res_1 := math.Float64bits(2) 
    res_2 := math.Float64bits(1) 
    res_3 := math.Float64bits(0) 
    res_4 := math.Float64bits(2.3) 
   
    // Displaying the result 
    fmt.Println("Result 1: ", res_1) 
    fmt.Println("Result 2: ", res_2) 
    fmt.Println("Result 3: ", res_3) 
    fmt.Println("Result 4: ", res_4) 
   
} 

输出：

Result 1: 4611686018427387904
Result 2: 4607182418800017408
Result 3: 0
Result 4: 4612361558371493478

示例 2：

// Golang program to illustrate 
// the use of math.Yn() function 
   
package main 
   
import ( 
    "fmt"
    "math"
) 
   
// Main function 
func main() { 
   
    // Finding the order-n Bessel 
    // function of the second kind 
    // Using Yn() function 
    res_1 := math.Yn(-3, -2) 
    res_2 := math.Yn(6, 3) 
    res_3 := math.Yn(1, 1.1) 
    res_4 := math.Yn(1, math.NaN()) 
    res_5 := math.Yn(-1, 0) 
   
    // Displaying the result 
    fmt.Println("Result 1: ", res_1) 
    fmt.Println("Result 2: ", res_2) 
    fmt.Println("Result 3: ", res_3) 
    fmt.Println("Result 4: ", res_4) 
    fmt.Println("Result 5: ", res_5) 
   
} 

输出：

Result 1:  NaN
Result 2:  -5.436470340703773
Result 3:  -0.698119560067667
Result 4:  NaN
Result 5:  +Inf