const.go 2.0 KB

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  1. // Copyright 2009 The Go Authors. All rights reserved.
  2. // Use of this source code is governed by a BSD-style
  3. // license that can be found in the LICENSE file.
  4. // Package math provides basic constants and mathematical functions.
  5. package math
  6. // Mathematical constants.
  7. // Reference: http://oeis.org/Axxxxxx
  8. const (
  9. E = 2.71828182845904523536028747135266249775724709369995957496696763 // A001113
  10. Pi = 3.14159265358979323846264338327950288419716939937510582097494459 // A000796
  11. Phi = 1.61803398874989484820458683436563811772030917980576286213544862 // A001622
  12. Sqrt2 = 1.41421356237309504880168872420969807856967187537694807317667974 // A002193
  13. SqrtE = 1.64872127070012814684865078781416357165377610071014801157507931 // A019774
  14. SqrtPi = 1.77245385090551602729816748334114518279754945612238712821380779 // A002161
  15. SqrtPhi = 1.27201964951406896425242246173749149171560804184009624861664038 // A139339
  16. Ln2 = 0.693147180559945309417232121458176568075500134360255254120680009 // A002162
  17. Log2E = 1 / Ln2
  18. Ln10 = 2.30258509299404568401799145468436420760110148862877297603332790 // A002392
  19. Log10E = 1 / Ln10
  20. )
  21. // Floating-point limit values.
  22. // Max is the largest finite value representable by the type.
  23. // SmallestNonzero is the smallest positive, non-zero value representable by the type.
  24. const (
  25. MaxFloat32 = 3.40282346638528859811704183484516925440e+38 // 2**127 * (2**24 - 1) / 2**23
  26. SmallestNonzeroFloat32 = 1.401298464324817070923729583289916131280e-45 // 1 / 2**(127 - 1 + 23)
  27. MaxFloat64 = 1.797693134862315708145274237317043567981e+308 // 2**1023 * (2**53 - 1) / 2**52
  28. SmallestNonzeroFloat64 = 4.940656458412465441765687928682213723651e-324 // 1 / 2**(1023 - 1 + 52)
  29. )
  30. // Integer limit values.
  31. const (
  32. MaxInt8 = 1<<7 - 1
  33. MinInt8 = -1 << 7
  34. MaxInt16 = 1<<15 - 1
  35. MinInt16 = -1 << 15
  36. MaxInt32 = 1<<31 - 1
  37. MinInt32 = -1 << 31
  38. MaxInt64 = 1<<63 - 1
  39. MinInt64 = -1 << 63
  40. MaxUint8 = 1<<8 - 1
  41. MaxUint16 = 1<<16 - 1
  42. MaxUint32 = 1<<32 - 1
  43. MaxUint64 = 1<<64 - 1
  44. )