MQL4参考 标准常量,列举和架构 命名常量 数值类型常量

Numerical Type Constants

Each simple numerical type is intended for a certain type of tasks and allows optimizing the operation of a mql4-program when used correctly. For a better code readability and correct handling of calculation results, there are constants which allow to receive information about restrictions set to a certain type of simple data.

Constant

Description

Value

CHAR_MIN

Minimal value, which can be represented by char type

-128

CHAR_MAX

Maximal value, which can be represented by char type

127

UCHAR_MAX

Maximal value, which can be represented by uchar type

255

SHORT_MIN

Minimal value, which can be represented by short type

-32768

SHORT_MAX

Maximal value, which can be represented by short type

32767

USHORT_MAX

Maximal value, which can be represented by ushort type

65535

INT_MIN

Minimal value, which can be represented by int type

-2147483648

INT_MAX

Maximal value, which can be represented by int type

2147483647

UINT_MAX

Maximal value, which can be represented by uint type

4294967295

LONG_MIN

Minimal value, which can be represented by long type

-9223372036854775808

LONG_MAX

Maximal value, which can be represented by long type

9223372036854775807

ULONG_MAX

Maximal value, which can be represented by ulong type

18446744073709551615

DBL_MIN

Minimal positive value, which can be represented by double type

2.2250738585072014e-308

DBL_MAX

Maximal value, which can be represented by double type

1.7976931348623158e+308

DBL_EPSILON

Minimal value, which satisfies the condition:

1.0+DBL_EPSILON != 1.0 (for double type)

2.2204460492503131e-016

DBL_DIG

Number of significant decimal digits for double type

15

DBL_MANT_DIG

Number of bits in a mantissa for double type

53

DBL_MAX_10_EXP

Maximal decimal value of exponent degree for double type

308

DBL_MAX_EXP

Maximal binary value of exponent degree for double type

1024

DBL_MIN_10_EXP

Minimal decimal value of exponent degree for double type

(-307)

DBL_MIN_EXP

Minimal binary value of exponent degree for double type

(-1021)

FLT_MIN

Minimal positive value, which can be represented by float type

1.175494351e-38

FLT_MAX

Maximal value, which can be represented by float type

3.402823466e+38

FLT_EPSILON

Minimal value, which satisfies the condition:

1.0+DBL_EPSILON != 1.0 (for float type)

1.192092896e-07

FLT_DIG

Number of significant decimal digits for float type

6

FLT_MANT_DIG

Number of bits in a mantissa for float type

24

FLT_MAX_10_EXP

Maximal decimal value of exponent degree for float type

38

FLT_MAX_EXP

Maximal binary value of exponent degree for float type

128

FLT_MIN_10_EXP

Minimal decimal value of exponent degree for float type

-37

FLT_MIN_EXP

Minimal binary value of exponent degree for float type

(-125)

Example:

void OnStart()
  {
//--- print the constant values
   printf("CHAR_MIN = %d",CHAR_MIN);
   printf("CHAR_MAX = %d",CHAR_MAX);
   printf("UCHAR_MAX = %d",UCHAR_MAX);
   printf("SHORT_MIN = %d",SHORT_MIN);
   printf("SHORT_MAX = %d",SHORT_MAX);
   printf("USHORT_MAX = %d",USHORT_MAX);
   printf("INT_MIN = %d",INT_MIN);
   printf("INT_MAX = %d",INT_MAX);
   printf("UINT_MAX = %u",UINT_MAX);
   printf("LONG_MIN = %I64d",LONG_MIN);
   printf("LONG_MAX = %I64d",LONG_MAX);
   printf("ULONG_MAX = %I64u",ULONG_MAX);
   printf("EMPTY_VALUE = %.16e",EMPTY_VALUE);
   printf("DBL_MIN = %.16e",DBL_MIN);
   printf("DBL_MAX = %.16e",DBL_MAX);
   printf("DBL_EPSILON = %.16e",DBL_EPSILON);
   printf("DBL_DIG = %d",DBL_DIG);
   printf("DBL_MANT_DIG = %d",DBL_MANT_DIG);
   printf("DBL_MAX_10_EXP =  %d",DBL_MAX_10_EXP);
   printf("DBL_MAX_EXP = %d",DBL_MAX_EXP);
   printf("DBL_MIN_10_EXP = %d",DBL_MIN_10_EXP);
   printf("DBL_MIN_EXP = %d",DBL_MIN_EXP);
   printf("FLT_MIN = %.8e",FLT_MIN);
   printf("FLT_MAX = %.8e",FLT_MAX);
   printf("FLT_EPSILON = %.8e",FLT_EPSILON);
  }