/// <summary>
/// Parses a string to produce a <see cref="Complex"/> object.
/// </summary>
/// <param name="source">the string to parse</param>
/// <param name="pos">input/ouput parsing parameter.</param>
/// <returns>the parsed <c>Complex</c> object.</returns>
public Complex parse(String source, Int32 pos)
{
int initialIndex = pos;
// parse whitespace
Int32 nonSpace = CompositeFormat.parseAndIgnoreWhitespace(source, pos);
// parse real
Double re = CompositeFormat.parseNumber(source, CultureInfo.CurrentCulture);
if (Double.IsNaN(re))
{
// invalid real number
// set index back to initial, error index should already be set
return(null);
}
// parse sign
Int32 p = CompositeFormat.parseNextCharacter(source, nonSpace);
char c = source[p];
int sign = 0;
switch (c)
{
case '0':
// no sign
// return real only complex number
return(new Complex(re, 0.0));
case '-':
sign = -1;
break;
case '+':
sign = 1;
break;
default:
// invalid sign
// set index back to initial, error index should be the last
// character examined.
return(null);
}
// parse whitespace
CompositeFormat.parseAndIgnoreWhitespace(source, pos);
// parse imaginary
Double im = CompositeFormat.parseNumber(source, CultureInfo.CurrentCulture);
if (Double.IsNaN(im))
{
// invalid imaginary number
// set index back to initial, error index should already be set
return(null);
}
// parse imaginary character
if (!CompositeFormat.parseFixedstring(source, getImaginaryCharacter()))
{
return(null);
}
return(new Complex(re, im * sign));
}
