PYL 106: Fitting the Spring Data

Finally let us fix the phase constant f, which determines what part of the cycle we begin with. Recall that the phase must be expressed in radians; hence the phase constant will be some number between 0 and 2p. One approach is simply using trial and error. After adjusting this parameter, the two curves should begin in the same part of the cycle. Another approach for finding this phase constant parameter is to invert the formula, giving f = cos -1 [ ( y (0) - yeq ) / A ] , (You must be in radians!) This approach does not always work, especially if the y(0) data point is not good. NEXT BACK