Documentation
¶
Overview ¶
Package math provides generic arithmetic functions
It intentionally does not support floating point types, as that would require reflect in generic code, for special handling of NaN, ±∞ and -0. Use the standard library math package instead.
Index ¶
- Constants
- func Abs[T constraints.Signed](v T) T
- func ChineseRemainder[T constraints.Integer](a, b, m, n T) (x T, ok bool)
- func Cmp[T TotallyOrdered](a, b T) int
- func Div[T constraints.Integer](a, b T) (q, r T)
- func GCD[T constraints.Integer](a, b T) (z, x, y T)
- func LCM[T constraints.Integer](a, b T) T
- func Max[T TotallyOrdered](a, b T) T
- func Min[T TotallyOrdered](a, b T) T
- func Sgn[T constraints.Signed](v T) T
- type TotallyOrdered
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 )
Mathematical constants.
const ( MaxFloat32 = 0x1p127 * (1 + (1 - 0x1p-23)) // 3.40282346638528859811704183484516925440e+38 SmallestNonzeroFloat32 = 0x1p-126 * 0x1p-23 // 1.401298464324817070923729583289916131280e-45 MaxFloat64 = 0x1p1023 * (1 + (1 - 0x1p-52)) // 1.79769313486231570814527423731704356798070e+308 SmallestNonzeroFloat64 = 0x1p-1022 * 0x1p-52 // 4.9406564584124654417656879286822137236505980e-324 )
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 ( MaxInt = 1<<(intSize-1) - 1 // MaxInt32 or MaxInt64 depending on intSize. MinInt = -1 << (intSize - 1) // MinInt32 or MinInt64 depending on intSize. MaxInt8 = 1<<7 - 1 // 127 MinInt8 = -1 << 7 // -128 MaxInt16 = 1<<15 - 1 // 32767 MinInt16 = -1 << 15 // -32768 MaxInt32 = 1<<31 - 1 // 2147483647 MinInt32 = -1 << 31 // -2147483648 MaxInt64 = 1<<63 - 1 // 9223372036854775807 MinInt64 = -1 << 63 // -9223372036854775808 MaxUint = 1<<intSize - 1 // MaxUint32 or MaxUint64 depending on intSize. MaxUint8 = 1<<8 - 1 // 255 MaxUint16 = 1<<16 - 1 // 65535 MaxUint32 = 1<<32 - 1 // 4294967295 MaxUint64 = 1<<64 - 1 // 18446744073709551615 )
Integer limit values.
Variables ¶
This section is empty.
Functions ¶
func ChineseRemainder ¶
func ChineseRemainder[T constraints.Integer](a, b, m, n T) (x T, ok bool)
ChineseRemainder solves the Chinese Remainder Theorem. The return value satisfies
x = a (mod m) x = b (mod n) 0 <= x < LCM(m, n)
If such an x exists.
It panics if m≤0 or n≤0.
func Cmp ¶
func Cmp[T TotallyOrdered](a, b T) int
Cmp returns -1, 0 and 1, if a < b, a == b and a > b, respectively.
func Div ¶
func Div[T constraints.Integer](a, b T) (q, r T)
Div returns p, q such that a = b•q+r, with 0≤r<|b|. It panics if b is 0.
func GCD ¶
func GCD[T constraints.Integer](a, b T) (z, x, y T)
GCD returns z, x, y, such that gcd(a, b) == z == a*x+b*y.
a and b may be positive, zero or negative.
If a == b == 0, GCD sets z = x = y = 0.
If a == 0 and b != 0, GCD sets z = |b|, x = 0, y = sign(b) * 1.
If a != 0 and b == 0, GCD sets z = |a|, x = sign(a) * 1, y = 0.
func LCM ¶
func LCM[T constraints.Integer](a, b T) T
LCM returns the least common multiple of a and b.
func Sgn ¶
func Sgn[T constraints.Signed](v T) T
Sgn returns -1, 0, 1 if v < 0, v == 0, v > 0, respectively.
Types ¶
type TotallyOrdered ¶
type TotallyOrdered interface {
constraints.Integer | ~string
}
Source Files