Rows contained in other rows

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Alberto Rocha 2017-2-16

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评论： Alberto Rocha 2017-2-22

I have a matrix such as A=[1 2 3;1 3 5] and I want to determine which row(s) is(are) totally contained in one (or more) single row(s) of another matrix such as B=[1 4 3 2 8;1 4 5 9;1 2 5 8 9]. In this example, row 1 of A is contained is the first row of B, but second row of A is NOT contained in a single row of B (elements 1 and 3 are in first row of B, and element 5 is in second). I know I could use ISMEMBER function for each row of A, but my matrices are too large, and a loop would take too long. Does anyone have a solution for that without a FOR-END or WHILE-END loop?

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Image Analyst 2017-2-16

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此回答的直接链接

https://ww2.mathworks.cn/matlabcentral/answers/325481-rows-contained-in-other-rows#answer_255135

normxcorr2_demo.m

How large? What are your actual, typical size dimensions for A and B? I just did a for loop with a million iterations and the for loop itself (not with ismember in it) took 0.002 seconds.

One way to do it with 2-D arrays is to use normalized cross correlation with normxcorr2(). See attached demo.