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FormatDoubleToString

Header:	STD.h
Namespace:	avl
Module:	FoundationLite

Creates a string from a double number using a proper format.

Applications: Useful for preparing a number for display or communication with specific number of fractional digits, sign etc.

Syntax

void avl::FormatDoubleToString
(
	double inDouble,
	const int inIntegerDigitCount,
	const int inFractionalDigitCount,
	const atl::String& inDecimalMark,
	const atl::String& inTrailingCharacter,
	const bool inForceSignPrinting,
	const atl::String& inSuffix,
	atl::String& outString
)

Parameters

Name	Type	Range	Default	Description
inDouble	double			Input real
inIntegerDigitCount	const int	0 - 1000		How many characters the integer part of the input real should have at least
inFractionalDigitCount	const int	0 - 100	3	How many characters the fractional part of the input real should have
inDecimalMark	const String&		\".\"	The symbol used to separate the integer part from the fractional part of the number
inTrailingCharacter	const String&		\"0\"	Defines the trailing character
inForceSignPrinting	const bool		False	Forces printing the sign of the number even if the number is positive
inSuffix	const String&		\"\"	Defines a suffix. Generally it is an unit of value (e.g. mm)
outString	String&			Output string

Examples


inDouble = 2.7182818284590452 inIntegerDigitCount = 2 inFractionalDigitCount = 2 inDecimalMark = "," inTrailingCharacter = "0" inForceSignPrinting = False inSuffix = "..."	outString = "02,72..."

In the first example desired integer digit count equals 2 as entered in inIntegerDigitCount, so the filter attaches character in inTrailingCharacter (zero) at the beginning of the result outString. Decimal mark is set as a comma and the number of fractional digits as 2.
The result string ends with ellipsis defined in inSuffix and the result is "02,72...".
Note that the second digit was rounded up to "2" due to the succeeding digit.


inDouble = 77 inIntegerDigitCount = 1 inFractionalDigitCount = 1 inDecimalMark = "." inTrailingCharacter = "#" inForceSignPrinting = True inSuffix = "°"	outString = "+77.0°"

The second example demonstrates formatting with one integer digit and one fractional. Note that the integer part of the formatted number is less than the value, but it doesn't affect to this part (unlike fractional part which can cuts off excessing digits).
Trailing character (#) doesn't affect to anything, because desired integer digit count described by inIntegerDigitCount is one (the same effect would be for zero).

Remarks

If you want to cut off excessing digits from a fractional part of a number (instead of rounding them), you can format a number with one extra precision digit and then use Substring to cut off the last digit. You can add a suffix manually by using AvsFilter_ConcatenateStrings.

Errors

List of possible exceptions: