go/src/pkg/math/const.go

// Copyright 2009 The Go Authors. All rights reserved.
// Use of this source code is governed by a BSD-style
// license that can be found in the LICENSE file.

// The math package provides basic constants and mathematical functions.
package math

// Mathematical constants.
// Reference: http://www.research.att.com/~njas/sequences/Axxxxxx
const (
	E	= 2.71828182845904523536028747135266249775724709369995957496696763;	// A001113
	Pi	= 3.14159265358979323846264338327950288419716939937510582097494459;	// A000796
	Phi	= 1.61803398874989484820458683436563811772030917980576286213544862;	// A001622

	Sqrt2	= 1.41421356237309504880168872420969807856967187537694807317667974;	// A002193
	SqrtE	= 1.64872127070012814684865078781416357165377610071014801157507931;	// A019774
	SqrtPi	= 1.77245385090551602729816748334114518279754945612238712821380779;	// A002161
	SqrtPhi	= 1.27201964951406896425242246173749149171560804184009624861664038;	// A139339

	Ln2	= 0.693147180559945309417232121458176568075500134360255254120680009;	// A002162
	Log2E	= 1/Ln2;
	Ln10	= 2.30258509299404568401799145468436420760110148862877297603332790;	// A002392
	Log10E	= 1/Ln10;
)

// Floating-point limit values.
// Max is the largest finite value representable by the type.
// Min is the smallest nonzero value representable by the type.
const (
	MaxFloat32	= 3.40282346638528859811704183484516925440e+38;		/* 2^127 * (2^24 - 1) / 2^23 */
	MinFloat32	= 1.401298464324817070923729583289916131280e-45;	/* 1 / 2^(127 - 1 + 23) */

	MaxFloat64	= 1.797693134862315708145274237317043567981e+308;	/* 2^1023 * (2^53 - 1) / 2^52 */
	MinFloat64	= 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;
)

// BUG(rsc): The manual should define the special cases for all of these functions.