Calculate probability of number appearing in a column
3 visualizaciones (últimos 30 días)
Mostrar comentarios más antiguos
I have a 1000x296 matrix called Values. The rows represent trials of a simulation, and the rows represent the rank (1-296) of a particular element.
I want to create a matrix that returns the probability of a column having a particular value. I assume i will need a set of nested for loops to count the number of times each value appears in each column, and then divide by the number of rows (1000).
E.g.
The value in cell (1,1) will have the probability of a particular row of column 1 having value 1
The value in cell (1,15) will have the probability of a particular row of column 1 having value 15
The value in cell (200, 155) will have the probability of a particular row of column 200 having value 155.
Thanks!
3 comentarios
Walter Roberson
el 22 de Nov. de 2019
Neither accumarray nor histcounts2 calculate probability distributions. In its simplest form, accumarray just counts.
Respuestas (2)
Image Analyst
el 21 de Nov. de 2019
Just loop over the array getting the histogram in each column.
Something like (untested)
numBins = 25; % Whatever you want.
edges = linspace(0, max(Values(:), numBins);
[rows, columns] = size(Values);
allCounts = zeros(numBins, columns);
for col = 1 : columns
thisColumn = Values(:, col);
counts = histcounts(thisColumns, edges);
allCounts(:, col) = allCounts(:, col) + counts;
end
% Normalize
allCounts = allCounts / sum(allCounts(:));
bar3(allCounts); % Display
0 comentarios
Walter Roberson
el 23 de Nov. de 2019
[rowidx, colidx] = ndgrid(1:size(Values,1), 1:size(Values,2));
probs = accumarray([colidx(:), Values(:)],1) ./ size(Values,1);;
0 comentarios
Ver también
Categorías
Más información sobre Loops and Conditional Statements en Help Center y File Exchange.
Community Treasure Hunt
Find the treasures in MATLAB Central and discover how the community can help you!
Start Hunting!