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# Array

Atoms, lists, and tables are all arrays. All nouns in J are arrays. Atoms have 0 dimensions, lists have 1 dimension, and tables have 2 dimensions. This extends to higher dimension arrays.

The primitive `$`, discussed earlier with lists and tables also works with higher dimension arrays.

       2 3 4 $ i. 24
     0  1  2  3
     4  5  6  7
     8  9 10 11

    12 13 14 15
    16 17 18 19
    20 21 22 23

The above is a 3-dimensional array. The blank line indicates the break between the 1st dimension and the 2nd and 3rd.

       b =. 2 3 4 $ 'abcdef'
       $ b
    2 3 4

The monad `i.` also works with higher dimension arrays.

       i. 2 3 4
     0  1  2  3
     4  5  6  7
     8  9 10 11

    12 13 14 15
    16 17 18 19
    20 21 22 23

The J terms atom, list, and table are analogous to the math terms of scalar, vector, and matrix.

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