MQL4参考 标准常量,列举和架构 命名常量 数学常量

Mathematical Constants

Special constants containing values are reserved for some mathematical expressions. These constants can be used in any place of the program instead of calculating their values using mathematical functions.

Constant

Description

Value

M_E

e

2.71828182845904523536

M_LOG2E

log2(e)

1.44269504088896340736

M_LOG10E

log10(e)

0.434294481903251827651

M_LN2

ln(2)

0.693147180559945309417

M_LN10

ln(10)

2.30258509299404568402

M_PI

pi

3.14159265358979323846

M_PI_2

pi/2

1.57079632679489661923

M_PI_4

pi/4

0.785398163397448309616

M_1_PI

1/pi

0.318309886183790671538

M_2_PI

2/pi

0.636619772367581343076

M_2_SQRTPI

2/sqrt(pi)

1.12837916709551257390

M_SQRT2

sqrt(2)

1.41421356237309504880

M_SQRT1_2

1/sqrt(2)

0.707106781186547524401

Example:

//+------------------------------------------------------------------+
//| Script program start function                                    |
//+------------------------------------------------------------------+
void OnStart()
  {
//--- print the values of constants
   Print("M_E = ",DoubleToString(M_E,16));
   Print("M_LOG2E = ",DoubleToString(M_LOG2E,16));
   Print("M_LOG10E = ",DoubleToString(M_LOG10E,16));
   Print("M_LN2 = ",DoubleToString(M_LN2,16));
   Print("M_LN10 = ",DoubleToString(M_LN10,16));
   Print("M_PI = ",DoubleToString(M_PI,16));
   Print("M_PI_2 = ",DoubleToString(M_PI_2,16));
   Print("M_PI_4 = ",DoubleToString(M_PI_4,16));
   Print("M_1_PI = ",DoubleToString(M_1_PI,16));
   Print("M_2_PI = ",DoubleToString(M_2_PI,16));
   Print("M_2_SQRTPI = ",DoubleToString(M_2_SQRTPI,16));
   Print("M_SQRT2 = ",DoubleToString(M_SQRT2,16));
   Print("M_SQRT1_2 = ",DoubleToString(M_SQRT1_2,16));
  }