;+ ; NAME: avg_nonzero.pro ; ; ; ; PURPOSE: ; compute a mean without having to use moment, and does not ; average in zeros ; ; INPUTS: ; data: an array that contains the data you with to average ; ; ; ; ; OPTIONAL INPUTS: ; dimension: tells which dimension to total over, see help for total ; ; ; KEYWORD PARAMETERS: ; NAN: pass nan to total() ; double: perform the avergaing in double, pased to total() ; ; ; OUTPUTS: ; the mean of the array ; ; ; EXAMPLE: ; a = [ [1.00000,1.00000,2.00000,3.00000], $ ; [4.00000,0.000000,6.00000,7.00000], $ ; [8.00000,9.00000,0.000000,11.0000], $ ; [12.0000,13.0000,14.0000,0.000000] ] ; IDL> print, avg_nonzero(a) ; 7.00000 ; IDL> print, avg_nonzero(a,1) ; 1.75000 5.66667 9.33333 13.0000 ; IDL> print, avg_nonzero(a,2) ; 6.25000 7.66667 7.33333 7.00000 ; ; ; MODIFICATION HISTORY: ; 3/28/2003 Brian Larsen ; - created ; ; 7/01/2007 Brian Larsen ; - fixed up ; ; 7/24/2007 Brian Larsen ; - rewritten much smarter from ; http://groups.google.com/group/comp.lang.idl-pvwave/browse_frm/thread/baf04086fc71d348/ee7ef51147d32797# ; ; ; ;- FUNCTION avg_nonzero, data, dimension, NAN=nan, DOUBLE=double if n_elements(data) eq 0 then $ message, /ioerror, 'avg_nonzero requires an input array' if n_elements(dimension) eq 0 then dimension=0 mean = total(data,dimension, NAN=nan, DOUBLE=double)/ $ (total(data<;1.,dimension, NAN=nan, DOUBLE=double) > 1.) return, mean END