MATLAB: How to mean all array

mean

Hi, im using matlab r2018a

lets say i have array

A = [NaN 1 1; 2 NaN 2; 1 NaN 2; 4 2 2]

how to get mean of all of it?

i need the result is 1.888889

i try using

z = mean(A(:))

but the answer is

z = NaN

Best Answer

A = [0 1 1; 2 3 2; 1 3 2; 4 2 2] ;
iwant = mean(A(:))
iwant = 1.9167

Related Solutions

MATLAB: Replace numbers in a matrix depending on neighbor numbers

Do you have the Image Processing Toolbox? If so, use isnan() and imreconstruct().

This works:

m = ...
[2 2 2 1 2 1 NaN NaN NaN;
  2 2 2 1 2 1 NaN NaN NaN;
  2 2 2 1 1 1 NaN NaN NaN;
  2 2 2 1 1 1 NaN NaN NaN;
  2 2 2 1 1 1 NaN NaN NaN;
  2 2 2 2 1 1 NaN NaN NaN;
  2 2 2 2 1 1 NaN NaN NaN;
  2 2 2 2 1 1 NaN NaN NaN;
  2 2 2 2 1 1 NaN NaN NaN;
  2 2 2 2 1 1 NaN NaN NaN;
  2 2 2 2 1 1 NaN NaN NaN;
  2 2 2 2 2 1 NaN NaN NaN;
  2 1 2 2 2 1 NaN NaN NaN;
  2 2 2 2 2 1 NaN NaN NaN]
m2 = m;
m2(isnan(m)) = 1
nansOnly = isnan(m)
mask = imreconstruct(nansOnly, m2 == 1)
% Make 1's nans
m2 = m; % Initialize
m2(mask) = nan % Set 1's touching nans to nan

MATLAB: Replace a number in a matrix depending on neighbor numbers

It is unclear if elements connected diagonally count as neighbours. If not, then you could try something like this.

%%Work with At to keep A intact
At=A;
%%Replace NaN with some number
At(isnan(At))=9;
%%B is for saving index of new NaNs
B=zeros(size(At));
%%Find sequences of [2 NaN] and [NaN 2] row-wise
for i=1:size(At,1)
B(i,strfind(At(i,:),[9 2])+1)=NaN;
B(i,strfind(At(i,:),[2 9]))=NaN;
end
%%Transpose A and repeat (same as column-wise)
At=At';
for i=1:size(At,2)
B(strfind(At(i,:),[9 2])+1,i)=NaN;
B(strfind(At(i,:),[2 9]),i)=NaN;
end
A(isnan(B))=NaN

ans =

   NaN   NaN   NaN   NaN   NaN   NaN   NaN
   NaN   NaN   NaN   NaN   NaN   NaN   NaN
   NaN   NaN     1     1     1   NaN   NaN
   NaN   NaN     1     2     1   NaN   NaN
   NaN   NaN     1     1     1   NaN   NaN
   NaN   NaN   NaN   NaN   NaN   NaN   NaN
   NaN   NaN   NaN   NaN   NaN   NaN   NaN

Best Answer

Related Solutions

MATLAB: Replace numbers in a matrix depending on neighbor numbers

MATLAB: Replace a number in a matrix depending on neighbor numbers

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