C(B) and D do have the same amount of elements (z=20), but the dimensions do not agree. Learn more about cell array;, logical indexing Both cell arrays are a series of double arrays which match in dimension between the cell arrays, but change size within the cell array. Ideally the Code would look like this: The values in C and D to be used in the equation have to be in the same row and column as in A. In MATLAB®, there are three primary approaches to accessing array elements based on their location (index) in the array. But amongst other things this depends on the actual size of your arrays, which we don't know. Accelerating the pace of engineering and science. (This is thoroughly discussed in the documentations ection on, If you want to efficiently convert subscripts to linear indices (this is frequently necessary if the subscripts are not continguous), use the, I am not certain exactly what you are doing, however the indexing scheme in my Answer works correctly, and the logical index. You can index into an array or a table using an array of logical indices. This does indeed work, but it seems that I do not fully understand how the logical indexing is working. "Logical" is one of the builtin types, or classes, of MATLAB matrices. It also returns true if A is an instance of a class that is derived from the logical class. Learn more about matlab, cell arrays MATLAB By testing your code ít does not seem that way. Whole array logical indexing: the mask must have the same shape as the array and the returned value is of rank 1 (a vector in Matlab). The problem is that the equation that calculates the values in A looks something like this. Logical Indexing of Cell Array containing matrices. If you are trying to calculate something like the following: As the above equation is only false for the first column, the logical Matrix B looks like this. I only want it to return logical true when they both satisfy the conditions and return logical true. MATLAB returns an array that matches the elements of the array X, element-by-element holding 1s where the matching values in X are the desired values, and 0s otherwise. Every technique that uses logical matrices as indexing of the entire array is going to have the same problem of being insensitive to order of the panes. It is possible that creating a large logical array via logical indexing could be slower than a loop. D is an 5x4 array. You can also select a web site from the following list: Select the China site (in Chinese or English) for best site performance. These approaches are â¦ https://www.mathworks.com/matlabcentral/answers/678563-manipulating-values-in-an-array-with-logical-indexing#answer_565493, https://www.mathworks.com/matlabcentral/answers/678563-manipulating-values-in-an-array-with-logical-indexing#comment_1183743, https://www.mathworks.com/matlabcentral/answers/678563-manipulating-values-in-an-array-with-logical-indexing#comment_1183803, https://www.mathworks.com/matlabcentral/answers/678563-manipulating-values-in-an-array-with-logical-indexing#comment_1183848, https://www.mathworks.com/matlabcentral/answers/678563-manipulating-values-in-an-array-with-logical-indexing#comment_1183983, https://www.mathworks.com/matlabcentral/answers/678563-manipulating-values-in-an-array-with-logical-indexing#comment_1184983, https://www.mathworks.com/matlabcentral/answers/678563-manipulating-values-in-an-array-with-logical-indexing#comment_1184988, https://www.mathworks.com/matlabcentral/answers/678563-manipulating-values-in-an-array-with-logical-indexing#answer_565483, https://www.mathworks.com/matlabcentral/answers/678563-manipulating-values-in-an-array-with-logical-indexing#comment_1183748. MathWorks is the leading developer of mathematical computing software for engineers and scientists. 0. That is, it is the position of each 1 in the logical matrix that determines which array element is being referred to. Reload the page to see its updated state. MathWorks is the leading developer of mathematical computing software for engineers and scientists. My answer was more intended as a kind of loud thinking, as I was not 100% sure how the assignment works and as my code does need some more complex manipulation. , a 1x10 array logical 1 ( true ) values where the condition is not an of! The action because of changes made to the number of dimensions each index refers. Be slower than a loop of double numbers, but have the class logical some. Types, or classes, of MATLAB matrices of your arrays, indexing can be classified considering following... Only want to access selected elements in arrays expressive features of MATLAB matrices of the builtin,! 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