Hi all,
I do not think that the proposed algorithm by Marcus is the correct way to implement this block,
because it assumes that the frequency has remained the same throughout the life of the block!
The correct way is to keep a state variable (say, "self.phase") that is initialized to 0 and records the accumulated state (modulo 2 pi) up to the last call of work.
Then in one call of work you should just generate the sin wave as suggested:
f_rel = 2 * np.pi * self.frequency / self.sample_rate
number = len(output_items[0])
phases = (f_rel * np.arange(0,number)+self.phase ) % (2*np.pi)
output_items[0][:] = self.amplitude*np.sin(phases)
self.phase=phases[-1]+
f_rel
best
Achilleas