Let the user provide custom weight into pyresample

From lavergne...@gmail.com on November 25, 2013 14:15:49

Hei pyresample team,

I am seating at the pytroll workshop, and would like a new feature:

Users could specify an array of weights (same dimension as lat/lon/data), and this weight would multiply the weight computed from distance (through the fov function, either _custom() or _gauss()).

Two use cases:

1. the weight could be given as 1./var(data) : the inverse of the uncertainty in each data point (as variance);
2. the weight could be computed on fov observation time, with more weight towards 12utc than at 0utc and 23:59utc. A resulting daily composite image would then be "sharpened towards 12utc", wrt to a daily composite without any weighting.

I'll start implementing right now :)
Thomas

Original issue: http://code.google.com/p/pyresample/issues/detail?id=12