Let A be a 3 by 5 matrix:
A=rand(3,5); v=1:5;How can I add v to each row of A without using a for loop, to improve efficiency?
MATLAB: Vector subtraction from matrix
MATLABperformancevectorization
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Although it is slightly different in operation, you could try this:
A = [1 0 5 4; 2 0 5 4; 3 4 6 2];N = sum(A(:));X = randn(N,1)/12;Y = randn(N,1)/12;[R,C] = find(A>0);B = A(A>0);X = X + cell2mat(arrayfun(@(z,m)repmat(z,m,1),C,B,'UniformOutput',false));Y = Y + cell2mat(arrayfun(@(z,m)repmat(z,m,1),R,B,'UniformOutput',false));scatter(X,Y,[],randperm(N),'filled')axis(gca,'ij')colormap('winter')which generates this figure:
The main differences from your code is that it generates all values at once (in the vectors X and Y) rather than within a loop, and it also uses a different random position for each point (rather than applying one random value to all points at each step of the while-loop). The code assumes that all values of A are positive integers or zero.
Are you using matrices or tables? It's not completely clear to me in your post. If it's a matrix you can do the calculation and concatenation in one step.
>> datosraw = [datosraw datosraw(:,1) * pi]This takes the original value of datosraw and concatenates it with the first column of datosraw * pi, placing that column at the end.
If you're using tables you can just assign the new table variable as the result of a calculation.
>> T T = promedio voltaje corriente ________ _______ _________ 0.119 0.81428 0.075854 0.49836 0.24352 0.05395 0.95974 0.92926 0.5308 0.34039 0.34998 0.77917 0.58527 0.1966 0.93401 0.22381 0.25108 0.12991 0.75127 0.61604 0.56882 0.2551 0.47329 0.46939 0.50596 0.35166 0.011902 0.69908 0.83083 0.33712 0.8909 0.58526 0.16218 0.95929 0.54972 0.79428 0.54722 0.91719 0.31122 0.13862 0.28584 0.52853 0.14929 0.7572 0.16565 0.25751 0.75373 0.60198 0.84072 0.38045 0.26297 0.25428 0.56782 0.65408 >> T.result = T.promedio * pi T = promedio voltaje corriente result ________ _______ _________ _______ 0.119 0.81428 0.075854 0.37384 0.49836 0.24352 0.05395 1.5657 0.95974 0.92926 0.5308 3.0151 0.34039 0.34998 0.77917 1.0694 0.58527 0.1966 0.93401 1.8387 0.22381 0.25108 0.12991 0.70313 0.75127 0.61604 0.56882 2.3602 0.2551 0.47329 0.46939 0.8014 0.50596 0.35166 0.011902 1.5895 0.69908 0.83083 0.33712 2.1962 0.8909 0.58526 0.16218 2.7989 0.95929 0.54972 0.79428 3.0137 0.54722 0.91719 0.31122 1.7191 0.13862 0.28584 0.52853 0.4355 0.14929 0.7572 0.16565 0.46902 0.25751 0.75373 0.60198 0.80899 0.84072 0.38045 0.26297 2.6412 0.25428 0.56782 0.65408 0.79885 >>
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