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QString QString::number ( double n, char format = 'g', int precision = 6 ) [static]

This is an overloaded member function, provided for convenience.
Returns a string equivalent of the number n, formatted according to the specified format and precision. The format can be 'f', 'F', 'e', 'E', 'g' or 'G' (see the arg() function documentation for an explanation of the formats).
Unlike QLocale::toString(), this function does not honor the user's locale settings.
See also setNum() and QLocale::toString().