1 May
2009
1 May
'09
6:28 p.m.
Suggestion for efficient way to apply a table lookup to each element of an integer array? import numpy as np _cos = np.empty ((2**rom_in_bits,), dtype=int) _sin = np.empty ((2**rom_in_bits,), dtype=int) for address in xrange (2**12): _cos[address] = nint ((2.0**(rom_out_bits-1)-1) * cos (2 * pi * address * (2.0**-rom_in_bits))) _sin[address] = nint ((2.0**(rom_out_bits-1)-1) * sin (2 * pi * address * (2.0**-rom_in_bits))) Now _cos, _sin are arrays of integers (quantized sin, cos lookup tables) How to apply _cos lookup to each element of an integer array: phase = np.array (..., dtype =int) cos_out = lookup (phase, _cos) ???