| public static LetterToHertz ( string letterString ) : float | ||
| letterString | string | The format of the string must be as follows: /// Starts with a Letter from A to G for the note. /// Next, optionaly a "#" or "b" for sharp or flat. /// Next, mandatorily, a digit of 0-8 for the octave. /// Examples: "C4" = middle C. "C#4" = middle c sharp. "Cb4" = middle c flat. C5 = high C. C3 = low C. /// octaves follow the weird musical convention of starting at C instead of at A. (i.e. C4 is one higher than B3, not B4) |
| return | float | |
public static float LetterToHertz(string letterString)
{
int len = letterString.Length;
if (len < 2 || len > 3)
return 0f;
int octave = (int)(letterString[len - 1] - '0');
string octaveLessNote = letterString.Substring(0,len-1).ToLower();
double referenceHz;
if (octave4Lookup.TryGetValue(octaveLessNote, out referenceHz))
{
int octaveDiff = octave - 4;
return (float)(referenceHz * Math.Pow(2.0, (double)octaveDiff));
}
return 0f; // bogus when input was garbage
}