4.6: Concatinating 2D Arrays

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Page ID: 136624

Zara Noroozi
Irvine Valley College

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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

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