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. array, but, unlike the vectors and matrices we have used so far, elements in cell arrays are cells that can store different types of values. This would also work if you were calculating a vector each time through the loop and wanted to store it as another column. 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. All arrays in MATLAB are rectangular, in the sense that the component vectors along any dimension are all the same length. An array is, more generally, a vector, matrix, or higher dimensional grid of numbers. 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. The MATLAB environment uses the term matrix to indicate a variable containing real or complex numbers arranged in a two-dimensional grid. 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. How to store vectors with different size and how to access them. Learn more about array, cell arrays, vectorization, matrix manipulation MATLAB. x diag (A) returns a column vector of the main diagonal. How to store vectors with different size in a. k0 represents the main diagonal, k>0 is above the main diagonal, and k<0 is below the main diagonal. D diag (v,k) places the elements of vector v on the k th diagonal. I'm going to run it by hitting F5, which means save and run the current file. D diag (v) returns a square diagonal matrix with the elements of vector v on the main diagonal. So I want to actually see the results of this. 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. Now inside of this loop what we're going to do is say Y is equal to I plus rand. 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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