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4.6: Concatinating 2D Arrays

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    136624
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    Concatenation means joining arrays together. With matrices, we can concatenate horizontally or vertically.

    mat1 = [4 3 1; 3 8 6];
    mat3 = [2 3 4 5; 3 4 5 6];
    
    conMat1 = [mat1 mat3]   % horizontal concatenation
    conMat2 = [mat1, mat3]  % also horizontal concatenation

    Horizontal concatenation joins matrices side-by-side. To do this, the matrices must have the same number of rows.

    Vertical concatenation stacks matrices on top of each other. To do this, the matrices must have the same number of columns.

     

    Example \(\PageIndex{1}\)

    Concatenating two arrays vertically.

    A = [1 2 3; 4 5 6];
    B = [7 8 9; 10 11 12];
    C = [A; B] % vertical concatenation
    Solution
    C =
    
        1 2 3
        4 5 6
        7 8 9
        10 11 12

     

     

     


    4.6: Concatinating 2D Arrays is shared under a CC BY-NC-SA license and was authored, remixed, and/or curated by LibreTexts.

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