in case of a so called free network adjustment, the point types "new point" and "datum point" are valid. "Reference points" and "stochastic points" cannot be combined with "datum points".

The coordinates of "reference points" are known beforehand. These coordines will not be adjusted. "Stochastic points" are known positions having variances. These points are used within a so called dynamic network adjustment.

Depending on your network design, you can combine datum and new points (free network) or reference/stochastic and new points, if you like to adjust the network w.r.t. a known reference frame.

/Micha

THE PROJECT CONTAINS UNCOMBINABLE POINT TYPES.WHAT IS THE DIFFERENCES BETWEEN THE REFERENCE/DATUM/STOCHASTIC POINTS?