public WWDecimalFft(int numPoints)
{
if (!IsPowerOfTwo(numPoints) || numPoints < 2)
{
throw new ArgumentException("numPoints must be power of two integer and larger than 2");
}
mNumPoints = numPoints;
mWn = new WWDecimalComplex[mNumPoints];
for (int i = 0; i < mNumPoints; ++i)
{
decimal angle = -2.0M * WWDecimalMath.M_PI * i / mNumPoints;
mWn[i] = new WWDecimalComplex(WWDecimalMath.Cos(angle), WWDecimalMath.Sin(angle));
}
// mNumStage == log_2(mNumPoints)
int t = mNumPoints;
for (int i = 0; 0 < t; ++i)
{
t >>= 1;
mNumStage = i;
}
mBitReversalTable = new uint[mNumPoints];
for (uint i = 0; i < mNumPoints; ++i)
{
mBitReversalTable[i] = BitReversal(mNumStage, i);
}
}
public static void TestSin()
{
for (int i = -360; i <= 720; i += 30)
{
Console.WriteLine("sin({0})={1}", i, WWDecimalMath.Sin(WWDecimalMath.M_2PI * i / 180));
}
}