subscripted dimension mismatch
Thursday, February 21, 2019 2:11:36 PM
Ed

Following is an examplethat leads to this error message. In this case, 'A' has size 2x3, that is, 2 rows and 3 columns. Understand how Matlab stores Matrices: Indexing of matrices in Matlab In order to prevent this error, you must understand the basic indexing of matrices as performed by Matlab. The size of the range specified by the following, M :,:,j,i is defined by the Nzand Nxarguments to the call zeroswith which you pre-allocated the array. We cannot test this because the file containing your data is not given, but you can solve it yourself using the command size and making sure all your dimensions match. Things to check: your dimensions Nz etc. The only difference is that, when we interact with computers, our errors are immediately indicated to us.

In the case of matrices, we have just seen that the corresponding column vector was simply composed of the columns of the matrix placed one after the other. The vector 'B' has size 1x4, 1 row and 4 columns. If we number them from 1 to 24 and consider for clarity that a 3- dimensional matrix is a set of pages last dimension containing each of the matrices the first two dimensions , then they will be organized in this way: Therefore, these elements are organized in the vector column that corresponds to the matrix by increasing the first index of the matrix, then the second, then the third and the next ones if we worked with more than 3 dimensions. The assignment statement attempts to replace the second row of 'A' with the row vector 'B', but this is not possible because 'B' has 4 columns, and 'A' only has 3 columns. .

Basically, MatLab stores vectors and matrices, regardless of their dimension, as column vectors. In order to assign to the second row of 'A', you must use a vector with 3 columns. For example, the following matrix: 2 7 4 5 8 3 it is stored in a column vector formed by the columns of the matrix one column after another. Use the size command to check the dimensions of both elements and make sure they match. However, it is more difficult to see what happens when we manipulate arrays of more than 2 dimensions. . .

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