MATLAB actually supports n-dimensional matrices, so you can see how this can work for multiple dimensions. If your calculation is creating a matrix each time, you would then use a three-dimensional matrix, and so on. So each column might represent one time through your loop. If your column vector was 'composed of all the columns of the original matrix', then use the reshape () command to turn it from a column vector back into the original 2D matrix. When N is negative, shiftdim shifts the dimensions to the right and pads with singletons. When N is positive, shiftdim shifts the dimensions to the left and wraps the N leading dimensions to the end. This would also work if you were calculating a vector each time through the loop and wanted to store it as another column. b shiftdim (a,-2) As per the documenation, B shiftdim (X,N) shifts the dimensions of X by N. So this is a very simple example of a technique that is used all the time in MATLAB where you will just take the results and store them in a matrix for easy manipulation and use later. ![]() ![]() Now that it's done what we can do is come in here and say Plot (y), and we can see that on the graph here. And each time we keep adding another column to this. And what we'll see by scrolling up through the Command Window here is that at first, we have Y is equal to a 1 by 1, then a 1 by 2, 1 by 3. So every time through the loop now this statement is going to read Y element 1 or 2, or 3, or 4, is going to equal to the same thing it did before. So what we can do is come in here and say I want to make Y into a vector. That isn't going to do very well if we want to plot this data. Now what if we wanted to plot those? Well, every time through this loop we have overwritten the value of Y so we lost, like for instance, 9.528 when we generated 10.857. And we can see we've gone through this loop 10 times and gotten different values of Y. Reshape a matrix row-wise by transposing the result. Reshape V, which is a 1-by-4 row vector, into the 4-by-1 column. Reshape Symbolic Row Vector into Column Vector. I'm going to run it by hitting F5, which means save and run the current file. This MATLAB function returns the n1-by-n2 matrix, which has the same elements as A. So I want to actually see the results of this. To use reshape () command in Matlab, the used vector to create matrix must be fit to row and column number to desired matrix in reshape () like above. ndarray.reshape () returns a new view, or a copy (depends on the new shape). This works, but you will still have to do bnew b.reshape (-1, 1) to assign the reshaped copy to a variable as Ilja Everilä pointed out. So we're going to just have a random number generated-somewhere between 0 and 1-and add it to the current value of I, and end. where the system will automatically compute the correct shape instead '-1'. From vector to matrix reshape every ith rows for each column. Now inside of this loop what we're going to do is say Y is equal to I plus rand. Reshaping vector to n-d matrix in row-wise order. What we're going to do is say for I is equal 1 : 10, meaning that we're going to count from 1 to 10. In today's video on MATLAB basics, we're going to show how to store the results of a calculation inside of a vector, which is a special case of a matrix.
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