./guide
File accumulate.pro

Last modification date:

Fri Nov 19 11:20:49 2004

Add some data into an accum_struct. This procedure is in GUIDE because of the nature of system variables. They are passed by value and not by reference, which would make this inefficient as temporary copies are continuously made - both in calling this procedure and again in setting fields in !g.accumbuf. So, this procedure needs to optionally be aware of the global structure, although it will use a user supplied one. The data is : sum(wt*data) The times are summed: sum(teff), sum(tint) The wt is summed: sum(wt) The tsys_sq is : sqrt(sum(wt*Tsys^2)) This needs to eventually take into consideration any reference Tsys. When that happens Unipops does it this way: tsys_ref^2 = sum(teff)/sum(teff/Tsys_ref^2) f_delt is used as a check to see if the channel spacing matches the ongoing average. If not supplied, the check is not done. If a weight (wt) is not supplied, it will be teff/Tsys^2 If teff is not supplied, tint will be used in its place.

Version

$Id: accumulate.pro,v 1.1 2004/11/19 16:20:49 bgarwood Exp $

Parameters
data in, required float array	The data to add to the accumulation structure. It must have the same number of elements as the ongoing accumulation (if this is not the first one added in).
tint in, required float	Integration time.
tsys in, required float	System temperature.
teff in, optional float	Effective integration time.
f_delt in, optional float	Channel spacing.

Keywords
wt in, optional float	Weight to give this data.
accum_buf in, optional accum_struct structure	The structure to hold the results of this accumlation. Uses !g.accumbuf if not supplied here.
noweight in, optional boolean	If this is set, then the data all have a weight = 1.0. Because this can skip a couple of multiplication steps, it should be somewhat faster than simply calling this with wt=1.0.