./guide
ave.pro

Last modification date:

Wed Sep 28 13:27:12 2016

ave

procedure ave, accumnum, [/noclear], [/quiet], [wtarray=variable], [count=variable]

Get the average from an ongoing accumulation.

The result is put into the primary data container (buffer 0). The contents of the accum buffer are cleared as a consequence of calling ave, unless the noclear keyword is set.

Note: It is a good idea to use sclear to clear the accum buffer before using it the first time so that you can be certain it is starting from a cleared (empty) state.

Examples

Average some data

   sclear
   get,index=1
   accum
   get,index=2
   accum
   ave 
 

Average some data using another accum buffer

   sclear, 2 
   get,index=1
   accum, 2
   get,index=2
   accum, 2
   ave, 2
 

Average some data, look at an intermediate result

   sclear
   get,index=1
   accum
   get,index=2
   accum
   ave,/noclear  ; accum buffer is NOT clear here
   get,index=3
   accum
   ave     ; accum buffer IS clear here
 

Uses

accumave accumclear set_data_container data_free

Version

$Id$

Parameters
accumnum in integer (def. 0)	Use this accum buffer. Defaults to the primary buffer, 0. There are 4 buffers total so this value must be between 0 and 3, inclusive.

Keywords
noclear in, optional boolean (def. F)	When set, the contents of the accum buffer are not cleared. This is useful when you want to see what the current average is but also plan on continuing to add data to that average. If this is not set, you would need to restart the accumulation to average more data.
quiet in, optional boolean (def. F)	Normally, ave announces how many spectra were averaged. Setting this turns that announcement off. This is especially useful when multiple accum buffers are used within a procedure.
wtarray out, optional variable	This is the contents of the weight array at the time of the average - one value per channel. If no blanked data went into accumulation, then all values in wtarray will be the same. If an entire spectrum was blanked (e.g. bad data from the GBT Spectrometer) then that spectrum was ignored during the accumulation and again, all of the wtarray values will be the same. This quantity is only important if some channels were blanked in at least one spectrum in the accumulation and you expect to use the result of this accumulation at a later time in part of another accumulation. If you keep the wtarray around in an IDL variable, then you can use it again to weight this result in that new accumulation.
count out, optional variable	The number of spectra that have been averaged. Returns -1 on an error. If count=0 then the the PDC and wtarray are unchanged by this. procedure.