i=0 ai,bi,wi = -1.296 0.70542 1.44488
i=1 ai,bi,wi = -0.099915 0.474194 2.84812
i=2 ai,bi,wi = -0.7456 0.518196 0.011004
i=3 ai,bi,wi = 1.08555 0.593522 1.79327