29 lines
962 B
Plaintext
29 lines
962 B
Plaintext
1 NB. a stand-alone scalar value is an array without any axis
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1
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NB. invoking any array produces that array as the result
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{. array=: 1 3, 6#0 NB. create, name, then get head item of the array: 1 3 0 0 0 0 0 0
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1
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0 { array NB. another way to get the head item
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1
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aword=: 'there' NB. a literal array
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0 1 3 2 2 { aword NB. multiple items can be drawn in a single action
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three
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]twoD=: 3 5 $ 'abcdefghijklmnopqrstuvwxyz'
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abcde
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fghij
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klmno
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1 { twoD NB. item 1 from twoD - a list of three items
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fghij
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1 {"1 twoD NB. item 1 from each rank-1 item of twoD (i.e. column 1)
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bgl
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(<2 2){ twoD NB. bracket indexing is not used in J
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m
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'X' 1} aword NB. amend item 1
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tXere
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aword=: 'X' 1 4} aword NB. in-place amend of items 1 and 4
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tXerX
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'X' (0 0;1 1;2 2)} twoD NB. amend specified items
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Xbcde
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fXhij
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klXno
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