How to return a mean value with NaN values in the matrix?

I have written a piece of code which states if a number is > 1 or < 0.05 then it should return a NaN value:

if JumpHeightImpulse(i) > 1                            
    JumpHeightImpulse(i) = 0;                            
end

if JumpHeightImpulse(i) < 0.05                                      
    JumpHeightImpulse(i) = 0;                       
end

end

And then I have tried to find the mean and standard deviation of my values using nanmean and nanstd:

for i = 1:length(NoS);                                             
    for j = 1:4                                             
        A = CombinedData(CombinedData(:,2)==i,:);                    
        B = A(A(:,3)==j,:);                                       
        mean(i,j) = nanmean(B(:,5));                                        
        stdev(i,j) = nanstd(B(:,5));
    end
end

However when I input this it returns NaN values for the mean and st dev. Any ideas as to why this is? Thanks

[Iain]

We need more of the code. But you could try:

JumpHeightImpulse(JumpHeightImpulse > 1) = NaN;
JumpHeightImpulse(JumpHeightImpulse < 0.05) = NaN;
mean_vals = nanmean(JumpHeightImpulse);
std_vals = nanstd(JumpHeightImpulse);

[Image Analyst]

lain, make that an answer.

Answer 1

[Iain]

We need more of the code. But you could try:

JumpHeightImpulse(JumpHeightImpulse > 1) = NaN; JumpHeightImpulse(JumpHeightImpulse < 0.05) = NaN; mean_vals = nanmean(JumpHeightImpulse); std_vals = nanstd(JumpHeightImpulse);

Answer 2

[Andrei Bobrov]

% 1)
JumpHeightImpulse(JumpHeightImpulse < .5 | JumpHeightImpulse > 1) = nan;

% 2) CD - your CombinedData 
m = length(NoS);
n = 4;
sv = CD(all(bsxfun(@le,CD(:,2:3),[m,n]),2) & CD(:,2) > 0,[2,3,5]);
your_mean = accumarray(sv(:,1:2),sv(:,3),[m, n],@nanmean,nan);
your_std  = accumarray(sv(:,1:2),sv(:,3),[m, n],@nanstd,nan);