time   calls  line
                  1 function m = nanmean(x,dim)
                  2 %NANMEAN Mean value, ignoring NaNs.
                  3 %   M = NANMEAN(X) returns the sample mean of X, treating NaNs as missing
                  4 %   values.  For vector input, M is the mean value of the non-NaN elements
                  5 %   in X.  For matrix input, M is a row vector containing the mean value of
                  6 %   non-NaN elements in each column.  For N-D arrays, NANMEAN operates
                  7 %   along the first non-singleton dimension.
                  8 %
                  9 %   NANMEAN(X,DIM) takes the mean along dimension DIM of X.
                 10 %
                 11 %   See also MEAN, NANMEDIAN, NANSTD, NANVAR, NANMIN, NANMAX, NANSUM.
                 12 
                 13 %   Copyright 1993-2004 The MathWorks, Inc.
                 14 %   $Revision: 1.1.8.1 $  $Date: 2010/03/16 00:15:50 $
                 15 
                 16 % Find NaNs and set them to zero
            86   17 nans = isnan(x); 
            86   18 x(nans) = 0; 
                 19 
            86   20 if nargin == 1 % let sum deal with figuring out which dimension to use 
                 21     % Count up non-NaNs.
            85   22     n = sum(~nans); 
            85   23     n(n==0) = NaN; % prevent divideByZero warnings 
                 24     % Sum up non-NaNs, and divide by the number of non-NaNs.
            85   25     m = sum(x) ./ n; 
             1   26 else 
                 27     % Count up non-NaNs.
             1   28     n = sum(~nans,dim); 
             1   29     n(n==0) = NaN; % prevent divideByZero warnings 
                 30     % Sum up non-NaNs, and divide by the number of non-NaNs.
             1   31     m = sum(x,dim) ./ n; 
             1   32 end 

Other subfunctions in this file are not included in this listing.