Package math provides basic constants and mathematical functions.
This package does not guarantee bit-identical results across architectures.
abs.go acosh.go asin.go asinh.go atan.go atan2.go atanh.go bits.go cbrt.go const.go copysign.go dim.go erf.go erfinv.go exp.go exp_asm.go expm1.go floor.go frexp.go gamma.go hypot.go j0.go j1.go jn.go ldexp.go lgamma.go log.go log10.go log1p.go logb.go mod.go modf.go nextafter.go pow.go pow10.go remainder.go signbit.go sin.go sincos.go sinh.go sqrt.go tan.go tanh.go unsafe.go
Mathematical constants.
const (
E = 2.71828182845904523536028747135266249775724709369995957496696763 // https://oeis.org/A001113
Pi = 3.14159265358979323846264338327950288419716939937510582097494459 // https://oeis.org/A000796
Phi = 1.61803398874989484820458683436563811772030917980576286213544862 // https://oeis.org/A001622
Sqrt2 = 1.41421356237309504880168872420969807856967187537694807317667974 // https://oeis.org/A002193
SqrtE = 1.64872127070012814684865078781416357165377610071014801157507931 // https://oeis.org/A019774
SqrtPi = 1.77245385090551602729816748334114518279754945612238712821380779 // https://oeis.org/A002161
SqrtPhi = 1.27201964951406896425242246173749149171560804184009624861664038 // https://oeis.org/A139339
Ln2 = 0.693147180559945309417232121458176568075500134360255254120680009 // https://oeis.org/A002162
Log2E = 1 / Ln2
Ln10 = 2.30258509299404568401799145468436420760110148862877297603332790 // https://oeis.org/A002392
Log10E = 1 / Ln10
) Floating-point limit values. Max is the largest finite value representable by the type. SmallestNonzero is the smallest positive, non-zero value representable by the type.
const (
MaxFloat32 = 3.40282346638528859811704183484516925440e+38 // 2**127 * (2**24 - 1) / 2**23
SmallestNonzeroFloat32 = 1.401298464324817070923729583289916131280e-45 // 1 / 2**(127 - 1 + 23)
MaxFloat64 = 1.797693134862315708145274237317043567981e+308 // 2**1023 * (2**53 - 1) / 2**52
SmallestNonzeroFloat64 = 4.940656458412465441765687928682213723651e-324 // 1 / 2**(1023 - 1 + 52)
) Integer limit values.
const (
MaxInt8 = 1<<7 - 1
MinInt8 = -1 << 7
MaxInt16 = 1<<15 - 1
MinInt16 = -1 << 15
MaxInt32 = 1<<31 - 1
MinInt32 = -1 << 31
MaxInt64 = 1<<63 - 1
MinInt64 = -1 << 63
MaxUint8 = 1<<8 - 1
MaxUint16 = 1<<16 - 1
MaxUint32 = 1<<32 - 1
MaxUint64 = 1<<64 - 1
) func Abs(x float64) float64
Abs returns the absolute value of x.
Special cases are:
Abs(±Inf) = +Inf Abs(NaN) = NaN
func Acos(x float64) float64
Acos returns the arccosine, in radians, of x.
Special case is:
Acos(x) = NaN if x < -1 or x > 1
package main
import (
"fmt"
"math"
)
func main() {
fmt.Printf("%.2f", math.Acos(1))
}
func Acosh(x float64) float64
Acosh returns the inverse hyperbolic cosine of x.
Special cases are:
Acosh(+Inf) = +Inf Acosh(x) = NaN if x < 1 Acosh(NaN) = NaN
package main
import (
"fmt"
"math"
)
func main() {
fmt.Printf("%.2f", math.Acosh(1))
}
func Asin(x float64) float64
Asin returns the arcsine, in radians, of x.
Special cases are:
Asin(±0) = ±0 Asin(x) = NaN if x < -1 or x > 1
package main
import (
"fmt"
"math"
)
func main() {
fmt.Printf("%.2f", math.Asin(0))
}
func Asinh(x float64) float64
Asinh returns the inverse hyperbolic sine of x.
Special cases are:
Asinh(±0) = ±0 Asinh(±Inf) = ±Inf Asinh(NaN) = NaN
package main
import (
"fmt"
"math"
)
func main() {
fmt.Printf("%.2f", math.Asinh(0))
}
func Atan(x float64) float64
Atan returns the arctangent, in radians, of x.
Special cases are:
Atan(±0) = ±0 Atan(±Inf) = ±Pi/2
package main
import (
"fmt"
"math"
)
func main() {
fmt.Printf("%.2f", math.Atan(0))
}
func Atan2(y, x float64) float64
Atan2 returns the arc tangent of y/x, using the signs of the two to determine the quadrant of the return value.
Special cases are (in order):
Atan2(y, NaN) = NaN Atan2(NaN, x) = NaN Atan2(+0, x>=0) = +0 Atan2(-0, x>=0) = -0 Atan2(+0, x<=-0) = +Pi Atan2(-0, x<=-0) = -Pi Atan2(y>0, 0) = +Pi/2 Atan2(y<0, 0) = -Pi/2 Atan2(+Inf, +Inf) = +Pi/4 Atan2(-Inf, +Inf) = -Pi/4 Atan2(+Inf, -Inf) = 3Pi/4 Atan2(-Inf, -Inf) = -3Pi/4 Atan2(y, +Inf) = 0 Atan2(y>0, -Inf) = +Pi Atan2(y<0, -Inf) = -Pi Atan2(+Inf, x) = +Pi/2 Atan2(-Inf, x) = -Pi/2
package main
import (
"fmt"
"math"
)
func main() {
fmt.Printf("%.2f", math.Atan2(0, 0))
}
func Atanh(x float64) float64
Atanh returns the inverse hyperbolic tangent of x.
Special cases are:
Atanh(1) = +Inf Atanh(±0) = ±0 Atanh(-1) = -Inf Atanh(x) = NaN if x < -1 or x > 1 Atanh(NaN) = NaN
package main
import (
"fmt"
"math"
)
func main() {
fmt.Printf("%.2f", math.Atanh(0))
}
func Cbrt(x float64) float64
Cbrt returns the cube root of x.
Special cases are:
Cbrt(±0) = ±0 Cbrt(±Inf) = ±Inf Cbrt(NaN) = NaN
func Ceil(x float64) float64
Ceil returns the least integer value greater than or equal to x.
Special cases are:
Ceil(±0) = ±0 Ceil(±Inf) = ±Inf Ceil(NaN) = NaN
package main
import (
"fmt"
"math"
)
func main() {
c := math.Ceil(1.49)
fmt.Printf("%.1f", c)
}
func Copysign(x, y float64) float64
Copysign returns a value with the magnitude of x and the sign of y.
func Cos(x float64) float64
Cos returns the cosine of the radian argument x.
Special cases are:
Cos(±Inf) = NaN Cos(NaN) = NaN
package main
import (
"fmt"
"math"
)
func main() {
fmt.Printf("%.2f", math.Cos(math.Pi/2))
}
func Cosh(x float64) float64
Cosh returns the hyperbolic cosine of x.
Special cases are:
Cosh(±0) = 1 Cosh(±Inf) = +Inf Cosh(NaN) = NaN
package main
import (
"fmt"
"math"
)
func main() {
fmt.Printf("%.2f", math.Cosh(0))
}
func Dim(x, y float64) float64
Dim returns the maximum of x-y or 0.
Special cases are:
Dim(+Inf, +Inf) = NaN Dim(-Inf, -Inf) = NaN Dim(x, NaN) = Dim(NaN, x) = NaN
func Erf(x float64) float64
Erf returns the error function of x.
Special cases are:
Erf(+Inf) = 1 Erf(-Inf) = -1 Erf(NaN) = NaN
func Erfc(x float64) float64
Erfc returns the complementary error function of x.
Special cases are:
Erfc(+Inf) = 0 Erfc(-Inf) = 2 Erfc(NaN) = NaN
func Erfcinv(x float64) float64
Erfcinv returns the inverse of Erfc(x).
Special cases are:
Erfcinv(0) = +Inf Erfcinv(2) = -Inf Erfcinv(x) = NaN if x < 0 or x > 2 Erfcinv(NaN) = NaN
func Erfinv(x float64) float64
Erfinv returns the inverse error function of x.
Special cases are:
Erfinv(1) = +Inf Erfinv(-1) = -Inf Erfinv(x) = NaN if x < -1 or x > 1 Erfinv(NaN) = NaN
func Exp(x float64) float64
Exp returns e**x, the base-e exponential of x.
Special cases are:
Exp(+Inf) = +Inf Exp(NaN) = NaN
Very large values overflow to 0 or +Inf. Very small values underflow to 1.
func Exp2(x float64) float64
Exp2 returns 2**x, the base-2 exponential of x.
Special cases are the same as Exp.
func Expm1(x float64) float64
Expm1 returns e**x - 1, the base-e exponential of x minus 1. It is more accurate than Exp(x) - 1 when x is near zero.
Special cases are:
Expm1(+Inf) = +Inf Expm1(-Inf) = -1 Expm1(NaN) = NaN
Very large values overflow to -1 or +Inf.
func Float32bits(f float32) uint32
Float32bits returns the IEEE 754 binary representation of f.
func Float32frombits(b uint32) float32
Float32frombits returns the floating point number corresponding to the IEEE 754 binary representation b.
func Float64bits(f float64) uint64
Float64bits returns the IEEE 754 binary representation of f.
func Float64frombits(b uint64) float64
Float64frombits returns the floating point number corresponding the IEEE 754 binary representation b.
func Floor(x float64) float64
Floor returns the greatest integer value less than or equal to x.
Special cases are:
Floor(±0) = ±0 Floor(±Inf) = ±Inf Floor(NaN) = NaN
package main
import (
"fmt"
"math"
)
func main() {
c := math.Floor(1.51)
fmt.Printf("%.1f", c)
}
func Frexp(f float64) (frac float64, exp int)
Frexp breaks f into a normalized fraction and an integral power of two. It returns frac and exp satisfying f == frac × 2**exp, with the absolute value of frac in the interval [½, 1).
Special cases are:
Frexp(±0) = ±0, 0 Frexp(±Inf) = ±Inf, 0 Frexp(NaN) = NaN, 0
func Gamma(x float64) float64
Gamma returns the Gamma function of x.
Special cases are:
Gamma(+Inf) = +Inf Gamma(+0) = +Inf Gamma(-0) = -Inf Gamma(x) = NaN for integer x < 0 Gamma(-Inf) = NaN Gamma(NaN) = NaN
func Hypot(p, q float64) float64
Hypot returns Sqrt(p*p + q*q), taking care to avoid unnecessary overflow and underflow.
Special cases are:
Hypot(±Inf, q) = +Inf Hypot(p, ±Inf) = +Inf Hypot(NaN, q) = NaN Hypot(p, NaN) = NaN
func Ilogb(x float64) int
Ilogb returns the binary exponent of x as an integer.
Special cases are:
Ilogb(±Inf) = MaxInt32 Ilogb(0) = MinInt32 Ilogb(NaN) = MaxInt32
func Inf(sign int) float64
Inf returns positive infinity if sign >= 0, negative infinity if sign < 0.
func IsInf(f float64, sign int) bool
IsInf reports whether f is an infinity, according to sign. If sign > 0, IsInf reports whether f is positive infinity. If sign < 0, IsInf reports whether f is negative infinity. If sign == 0, IsInf reports whether f is either infinity.
func IsNaN(f float64) (is bool)
IsNaN reports whether f is an IEEE 754 “not-a-number” value.
func J0(x float64) float64
J0 returns the order-zero Bessel function of the first kind.
Special cases are:
J0(±Inf) = 0 J0(0) = 1 J0(NaN) = NaN
func J1(x float64) float64
J1 returns the order-one Bessel function of the first kind.
Special cases are:
J1(±Inf) = 0 J1(NaN) = NaN
func Jn(n int, x float64) float64
Jn returns the order-n Bessel function of the first kind.
Special cases are:
Jn(n, ±Inf) = 0 Jn(n, NaN) = NaN
func Ldexp(frac float64, exp int) float64
Ldexp is the inverse of Frexp. It returns frac × 2**exp.
Special cases are:
Ldexp(±0, exp) = ±0 Ldexp(±Inf, exp) = ±Inf Ldexp(NaN, exp) = NaN
func Lgamma(x float64) (lgamma float64, sign int)
Lgamma returns the natural logarithm and sign (-1 or +1) of Gamma(x).
Special cases are:
Lgamma(+Inf) = +Inf Lgamma(0) = +Inf Lgamma(-integer) = +Inf Lgamma(-Inf) = -Inf Lgamma(NaN) = NaN
func Log(x float64) float64
Log returns the natural logarithm of x.
Special cases are:
Log(+Inf) = +Inf Log(0) = -Inf Log(x < 0) = NaN Log(NaN) = NaN
func Log10(x float64) float64
Log10 returns the decimal logarithm of x. The special cases are the same as for Log.
func Log1p(x float64) float64
Log1p returns the natural logarithm of 1 plus its argument x. It is more accurate than Log(1 + x) when x is near zero.
Special cases are:
Log1p(+Inf) = +Inf Log1p(±0) = ±0 Log1p(-1) = -Inf Log1p(x < -1) = NaN Log1p(NaN) = NaN
func Log2(x float64) float64
Log2 returns the binary logarithm of x. The special cases are the same as for Log.
func Logb(x float64) float64
Logb returns the binary exponent of x.
Special cases are:
Logb(±Inf) = +Inf Logb(0) = -Inf Logb(NaN) = NaN
func Max(x, y float64) float64
Max returns the larger of x or y.
Special cases are:
Max(x, +Inf) = Max(+Inf, x) = +Inf Max(x, NaN) = Max(NaN, x) = NaN Max(+0, ±0) = Max(±0, +0) = +0 Max(-0, -0) = -0
func Min(x, y float64) float64
Min returns the smaller of x or y.
Special cases are:
Min(x, -Inf) = Min(-Inf, x) = -Inf Min(x, NaN) = Min(NaN, x) = NaN Min(-0, ±0) = Min(±0, -0) = -0
func Mod(x, y float64) float64
Mod returns the floating-point remainder of x/y. The magnitude of the result is less than y and its sign agrees with that of x.
Special cases are:
Mod(±Inf, y) = NaN Mod(NaN, y) = NaN Mod(x, 0) = NaN Mod(x, ±Inf) = x Mod(x, NaN) = NaN
func Modf(f float64) (int float64, frac float64)
Modf returns integer and fractional floating-point numbers that sum to f. Both values have the same sign as f.
Special cases are:
Modf(±Inf) = ±Inf, NaN Modf(NaN) = NaN, NaN
func NaN() float64
NaN returns an IEEE 754 “not-a-number” value.
func Nextafter(x, y float64) (r float64)
Nextafter returns the next representable float64 value after x towards y.
Special cases are:
Nextafter(x, x) = x Nextafter(NaN, y) = NaN Nextafter(x, NaN) = NaN
func Nextafter32(x, y float32) (r float32)
Nextafter32 returns the next representable float32 value after x towards y.
Special cases are:
Nextafter32(x, x) = x Nextafter32(NaN, y) = NaN Nextafter32(x, NaN) = NaN
func Pow(x, y float64) float64
Pow returns x**y, the base-x exponential of y.
Special cases are (in order):
Pow(x, ±0) = 1 for any x Pow(1, y) = 1 for any y Pow(x, 1) = x for any x Pow(NaN, y) = NaN Pow(x, NaN) = NaN Pow(±0, y) = ±Inf for y an odd integer < 0 Pow(±0, -Inf) = +Inf Pow(±0, +Inf) = +0 Pow(±0, y) = +Inf for finite y < 0 and not an odd integer Pow(±0, y) = ±0 for y an odd integer > 0 Pow(±0, y) = +0 for finite y > 0 and not an odd integer Pow(-1, ±Inf) = 1 Pow(x, +Inf) = +Inf for |x| > 1 Pow(x, -Inf) = +0 for |x| > 1 Pow(x, +Inf) = +0 for |x| < 1 Pow(x, -Inf) = +Inf for |x| < 1 Pow(+Inf, y) = +Inf for y > 0 Pow(+Inf, y) = +0 for y < 0 Pow(-Inf, y) = Pow(-0, -y) Pow(x, y) = NaN for finite x < 0 and finite non-integer y
package main
import (
"fmt"
"math"
)
func main() {
c := math.Pow(2, 3)
fmt.Printf("%.1f", c)
}
func Pow10(n int) float64
Pow10 returns 10**n, the base-10 exponential of n.
Special cases are:
Pow10(n) = 0 for n < -323 Pow10(n) = +Inf for n > 308
package main
import (
"fmt"
"math"
)
func main() {
c := math.Pow10(2)
fmt.Printf("%.1f", c)
}
func Remainder(x, y float64) float64
Remainder returns the IEEE 754 floating-point remainder of x/y.
Special cases are:
Remainder(±Inf, y) = NaN Remainder(NaN, y) = NaN Remainder(x, 0) = NaN Remainder(x, ±Inf) = x Remainder(x, NaN) = NaN
func Round(x float64) float64
Round returns the nearest integer, rounding half away from zero.
Special cases are:
Round(±0) = ±0 Round(±Inf) = ±Inf Round(NaN) = NaN
func RoundToEven(x float64) float64
RoundToEven returns the nearest integer, rounding ties to even.
Special cases are:
RoundToEven(±0) = ±0 RoundToEven(±Inf) = ±Inf RoundToEven(NaN) = NaN
func Signbit(x float64) bool
Signbit returns true if x is negative or negative zero.
func Sin(x float64) float64
Sin returns the sine of the radian argument x.
Special cases are:
Sin(±0) = ±0 Sin(±Inf) = NaN Sin(NaN) = NaN
package main
import (
"fmt"
"math"
)
func main() {
fmt.Printf("%.2f", math.Sin(math.Pi))
}
func Sincos(x float64) (sin, cos float64)
Sincos returns Sin(x), Cos(x).
Special cases are:
Sincos(±0) = ±0, 1 Sincos(±Inf) = NaN, NaN Sincos(NaN) = NaN, NaN
package main
import (
"fmt"
"math"
)
func main() {
sin, cos := math.Sincos(0)
fmt.Printf("%.2f, %.2f", sin, cos)
}
func Sinh(x float64) float64
Sinh returns the hyperbolic sine of x.
Special cases are:
Sinh(±0) = ±0 Sinh(±Inf) = ±Inf Sinh(NaN) = NaN
package main
import (
"fmt"
"math"
)
func main() {
fmt.Printf("%.2f", math.Sinh(0))
}
func Sqrt(x float64) float64
Sqrt returns the square root of x.
Special cases are:
Sqrt(+Inf) = +Inf Sqrt(±0) = ±0 Sqrt(x < 0) = NaN Sqrt(NaN) = NaN
package main
import (
"fmt"
"math"
)
func main() {
const (
a = 3
b = 4
)
c := math.Sqrt(a*a + b*b)
fmt.Printf("%.1f", c)
}
func Tan(x float64) float64
Tan returns the tangent of the radian argument x.
Special cases are:
Tan(±0) = ±0 Tan(±Inf) = NaN Tan(NaN) = NaN
package main
import (
"fmt"
"math"
)
func main() {
fmt.Printf("%.2f", math.Tan(0))
}
func Tanh(x float64) float64
Tanh returns the hyperbolic tangent of x.
Special cases are:
Tanh(±0) = ±0 Tanh(±Inf) = ±1 Tanh(NaN) = NaN
package main
import (
"fmt"
"math"
)
func main() {
fmt.Printf("%.2f", math.Tanh(0))
}
func Trunc(x float64) float64
Trunc returns the integer value of x.
Special cases are:
Trunc(±0) = ±0 Trunc(±Inf) = ±Inf Trunc(NaN) = NaN
func Y0(x float64) float64
Y0 returns the order-zero Bessel function of the second kind.
Special cases are:
Y0(+Inf) = 0 Y0(0) = -Inf Y0(x < 0) = NaN Y0(NaN) = NaN
func Y1(x float64) float64
Y1 returns the order-one Bessel function of the second kind.
Special cases are:
Y1(+Inf) = 0 Y1(0) = -Inf Y1(x < 0) = NaN Y1(NaN) = NaN
func Yn(n int, x float64) float64
Yn returns the order-n Bessel function of the second kind.
Special cases are:
Yn(n, +Inf) = 0 Yn(n ≥ 0, 0) = -Inf Yn(n < 0, 0) = +Inf if n is odd, -Inf if n is even Yn(n, x < 0) = NaN Yn(n, NaN) = NaN
| Name | Synopsis |
|---|---|
| .. | |
| big | Package big implements arbitrary-precision arithmetic (big numbers). |
| bits | Package bits implements bit counting and manipulation functions for the predeclared unsigned integer types. |
| cmplx | Package cmplx provides basic constants and mathematical functions for complex numbers. |
| rand | Package rand implements pseudo-random number generators. |
© Google, Inc.
Licensed under the Creative Commons Attribution License 3.0.
https://golang.org/pkg/math/