A MATLAB Warning Reported by the Code Analyzer — "Newline following comma acts as a row separator."

When creating a matrix in MATLAB, we should note that “Newline following comma acts as a row separator.” For example,

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A = [1, 2, 3, 4, 
    5, 6, 7, 8];

A

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A =
     1     2     3     4
     5     6     7     8

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A = [1, 2, 3, 4;
    5, 6, 7, 8];

we can see MATLAB Code Analyzer reports a warning message about it:

We can use the “line continuation” operator ...¹ to not make a newline:

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A = [1, 2, 3, 4, 
    5, 6, 7, 8];

B = [1, 2, 3, 4, ...
    5, 6, 7, 8];

A, B

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A =
     1     2     3     4
     5     6     7     8

B =
     1     2     3     4     5     6     7     8

This point looks very trivial, but it will lead some errors about matrix size if we don’t mention it when coding — actually, recently I spent much time to find an error brought by making a newline but without using ....

Besides, the case is the same when omitting commas:

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A = [1 2 3 4
    5 6 7 8];

B = [1 2 3 4 ...
    5 6 7 8];

A, B

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A =
     1     2     3     4
     5     6     7     8

B =
     1     2     3     4     5     6     7     8

References