2.5.0/html/Types_8h.html

#define NUMBER 12345.67890123456789012345678901

std::cout << NUMBER << '\n'; // default precision, writes: 12345.7


double d = NUMBER;

std::cout.precision(writtenDigits<double>(0.0)); // explicit template instantiation

std::cout << writtenDigits<double>(0.0) << ": " << d << '\n'; // writes: 15: 12345.6789012346


float r = NUMBER;

std::cout.precision(writtenDigits(r)); // type deduced from argument

std::cout << writtenDigits(r) << ": " << r << '\n'; // writes: 6: 12345.7


long double l = NUMBER;

std::cout.precision(writtenDigits(1L)); // argument is not used, but L suffix indicates a long double

std::cout << writtenDigits(1L) << ": " << l << '\n'; // writes: 18: 12345.6789012345671


double x = 88.99;

std::cout.precision(15);

std::cout << "15: " << x << '\n'; // writes: 15: 88.99

std::cout.precision(16);

std::cout << "16: " << x << '\n'; // writes: 16: 88.98999999999999
Namespaces
	OpenMS
	Main OpenMS namespace.

	OpenMS::Internal
	Namespace used to hide implementation details from users.
Typedefs
typedef OPENMS_INT32_TYPE	Int32
	Signed integer type (32bit) More...

typedef OPENMS_UINT32_TYPE	UInt32
	Unsigned integer type (32bit) More...

typedef OPENMS_INT64_TYPE	Int64
	Signed integer type (64bit) More...

typedef OPENMS_UINT64_TYPE	UInt64
	Unsigned integer type (64bit) More...

typedef time_t	Time
	Time type. More...

typedef unsigned int	UInt
	Unsigned integer type. More...

typedef int	Int
	Signed integer type. More...

typedef OPENMS_BYTE_TYPE	Byte
	Byte type. More...

typedef OPENMS_UINT64_TYPE	UID
	A unique object ID (as unsigned 64bit type). More...

typedef size_t	Size
	Size type e.g. used as variable which can hold result of size() More...

typedef ptrdiff_t	SignedSize
	Signed Size type e.g. used as pointer difference. More...
Enumerations
enum	ASCII { ASCII__BACKSPACE = '\b', ASCII__BELL = '\a', ASCII__CARRIAGE_RETURN = '\r', ASCII__HORIZONTAL_TAB = '\t', ASCII__NEWLINE = '\n', ASCII__RETURN = ASCII__NEWLINE, ASCII__SPACE = ' ', ASCII__TAB = ASCII__HORIZONTAL_TAB, ASCII__VERTICAL_TAB = '\v', ASCII__COLON = ':', ASCII__COMMA = ',', ASCII__EXCLAMATION_MARK = '!', ASCII__POINT = '.', ASCII__QUESTION_MARK = '?', ASCII__SEMICOLON = ';' }
Functions
Numbers of digits used for writing floating point numbers (a.k.a. precision).
These functions are provided to unify the handling of this issue throughout OpenMS. (So please don't use ad-hoc numbers ;-) ) If you want to avoid side effects you can use precisionWrapper() to write a floating point number with appropriate precision; in this case the original state of the stream is automatically restored afterwards. See precisionWrapper() for details. In practice, the number of decimal digits that the type can represent without loss of precision are 6 digits for single precision and 15 digits for double precision. We have $2^{24}/10^{6}=16.777216$ and $2^{53}/10^{15}=9.007199254740992$ , so rounding will remove the remaining difference. Example: #define NUMBER 12345.67890123456789012345678901 std::cout << NUMBER << '\n'; // default precision, writes: 12345.7 double d = NUMBER; std::cout.precision(writtenDigits<double>(0.0)); // explicit template instantiation std::cout << writtenDigits<double>(0.0) << ": " << d << '\n'; // writes: 15: 12345.6789012346 float r = NUMBER; std::cout.precision(writtenDigits(r)); // type deduced from argument std::cout << writtenDigits(r) << ": " << r << '\n'; // writes: 6: 12345.7 long double l = NUMBER; std::cout.precision(writtenDigits(1L)); // argument is not used, but L suffix indicates a long double std::cout << writtenDigits(1L) << ": " << l << '\n'; // writes: 18: 12345.6789012345671 double x = 88.99; std::cout.precision(15); std::cout << "15: " << x << '\n'; // writes: 15: 88.99 std::cout.precision(16); std::cout << "16: " << x << '\n'; // writes: 16: 88.98999999999999
template<typename FloatingPointType >
constexpr Int	writtenDigits (const FloatingPointType &=FloatingPointType())
	Number of digits commonly used for writing a floating point type (a.k.a. precision). Specializations are defined for float, double, long double. More...

template<>
constexpr Int	writtenDigits< float > (const float &)
	Number of digits commonly used for writing a `float` (a.k.a. precision). More...

template<>
constexpr Int	writtenDigits< double > (const double &)
	Number of digits commonly used for writing a `double` (a.k.a. precision). More...

template<>
constexpr Int	writtenDigits< int > (const int &)
	We do not want to bother people who unintentionally provide an int argument to this. More...

template<>
constexpr Int	writtenDigits< unsigned int > (const unsigned int &)
	We do not want to bother people who unintentionally provide an unsigned int argument to this. More...

template<>
constexpr Int	writtenDigits< long int > (const long int &)
	We do not want to bother people who unintentionally provide a long int argument to this. More...

template<>
constexpr Int	writtenDigits< unsigned long int > (const unsigned long int &)
	We do not want to bother people who unintentionally provide an unsigned long int argument to this. More...

template<>
constexpr Int	writtenDigits< DataValue > (const DataValue &)
	DataValue will be printed like double. More...

template<>
constexpr Int	writtenDigits< long double > (const long double &)
	Number of digits commonly used for writing a `long` `double` (a.k.a. precision). ... More...