The results of PMF are thus generally less ambiguous and, since profiles consist of positive peaks, easier to interpret. Rotations are not always totally eliminated, however, and it may be possible to get different solutions with different rotations. PMF gives several methods for the elimination of rotations by setting additional restrictions and thus ensuring a physically meaningful solution. In some cases one must settle for a range of possible solutions. Rotations are not a deficiency of the program, but indicate only that the data does not contain enough information to derive a single solution using the given model.
Velocity gradients make peaks appear in different locations in .
Since a single component cannot represent such a set of spectra, PMF represents them with several basic components. Spectra with one shifted peak would be approximated with several close-lying peaks in matrix , the relative intensities of which change according to the gradient. The gradient can in such cases be deduced from this gradual change of the weights, and even the central velocities in each spectrum can be calculated from the factorization. On the other hand, the inadequacy of the model makes it necessary to be very careful in the interpretation of the results. The Thumbprint nebula is an isolated and highly symmetrical Bok globule situated in the Chamaeleon III region.