Huh, I’ve never used the Interpolate Data component before, but the behavior of Cubic doesn’t seem to make any sense, either by the standard algorithm (as presented in Paul Bourke’s website) or @DavidRutten’s explanation
E.g. in the screenshot below, shouldn’t the interpolated interval between t_1 and t_2 be a cubic polynomial that passes through the four sample points circled in blue? It certainly doesn’t look that way though…
cubic-interpolation-oddity.gh (12.3 KB)