MATLAB: How to display averages in new array

arrayduplicate postmatrix arraymean

Hello, I want to average each column in 'B' and arrange the averages in an array so that each row of the new array will display the set of averages relating to the final stock price B(n+1,i).
Thats where I am having difficulty.Thank you for your efforts
n=4
i=1:16
B =
  Columns 1 through 11
    100.0000  100.0000  100.0000  100.0000  100.0000  100.0000  100.0000  100.0000  100.0000  100.0000  100.0000  
     90.0000   90.0000   90.0000   90.0000  110.0000   90.0000   90.0000   90.0000  110.0000  110.0000  110.0000   
     81.0000   81.0000   81.0000   99.0000   99.0000   81.0000   99.0000   99.0000   99.0000   99.0000  121.0000   
     72.9000   72.9000   89.1000   89.1000   89.1000   89.1000   89.1000  108.9000   89.1000  108.9000  108.9000  
     65.6100   80.1900   80.1900   80.1900   80.1900   98.0100   98.0100   98.0100   98.0100   98.0100   98.0100  
    Columns 12 through 16
    100.0000  100.0000  100.0000  100.0000  100.000   
    110.0000  110.0000  110.0000  110.0000  110.000
    121.0000  121.0000  121.0000  121.0000  121.000
    108.9000  133.1000  133.1000  108.9000  133.100
    119.7900  119.7900  119.7900  119.7900  146.410
Each column in B is a price trajectory of an asset, the asset moves up or down at each row, but some paths end up at the same point after n+1 time steps.
so I have multiple price paths ending at the same point.
I want to average the paths and group them together such that I will have a set of averages relating to one final stock price.
for example my new array A will look like
so A will look something like this
A=
   81.9020         0         0         0         0         0
   84.8100   88.0500   91.6500   95.6500         0         0
   91.6200   95.2200   99.1820   99.2200  103.1800  107.5800
  103.5300  107.5300  111.9300  116.7700         0         0
  122.1000         0         0         0         0         0
….. so each row of A displays the set of averages for each price path ending at the same point. row 1 of A has the averages for final stock price 65.61 row 2 of A has the averages for final stock price 80.19 for 2 of A has the averages for final stock price 98.01

Best Answer

OK, I changed it from a cell array to a double array like you wanted:
B=[100.0000  100.0000  100.0000  100.0000  100.0000  100.0000  100.0000  100.0000  100.0000  100.0000  100.0000  100.0000  100.0000  100.0000  100.0000  100.000;
  90.0000   90.0000   90.0000   90.0000  110.0000   90.0000   90.0000   90.0000  110.0000  110.0000  110.0000  110.0000  110.0000  110.0000  110.0000  110.000;
  81.0000   81.0000   81.0000   99.0000   99.0000   81.0000   99.0000   99.0000   99.0000   99.0000  121.0000  121.0000  121.0000  121.0000  121.0000  121.000;
  72.9000   72.9000   89.1000   89.1000   89.1000   89.1000   89.1000  108.9000   89.1000  108.9000  108.9000  108.9000  133.1000  133.1000  108.9000  133.100;
  65.6100   80.1900   80.1900   80.1900   80.1900   98.0100   98.0100   98.0100   98.0100   98.0100   98.0100  119.7900  119.7900  119.7900  119.7900  146.410]
% Extract the last row.
lastRow = B(end, :)
[rows, columns] = size(B)
% Get unique prices in the last row, for example [65.61, 80.19, 98.01]
pricesToSearchFor = unique(lastRow)
for k = 1 : length(pricesToSearchFor)
  thisPrice = pricesToSearchFor(k);
  fprintf('Searching all columns for price $%.2f.\n', thisPrice);
  % Search every column for this unique price.
  columnCounter = 1;
  for column = 1 : columns
    thisColumn = B(:, column);
    % Find out if this price occurs EXACTLY in the column
    lastIndexInColumn = find(thisColumn == thisPrice, 1, 'last');
    if ~isempty(lastIndexInColumn)
      fprintf('Found %.2f at row %d of column %d of B.\n', ...
        thisPrice, lastIndexInColumn, column);
      % If we found the price in this column, add it to a new column of A
      A(k, columnCounter) = mean(thisColumn(1:lastIndexInColumn));
      % Increment the column in A
      columnCounter = columnCounter + 1;
    end
  end
end
A
What it shows is:
A =
       81.902            0            0            0            0            0
       84.818       88.058       91.658       95.658            0            0
       91.622       95.222       99.182       99.222       103.18       107.58
       111.94       116.78       116.78       111.94            0            0
        122.1            0            0            0            0            0
Is this what you want?
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