Structuring of Arrays
Primitive functions that restructure arrays:
| symbol | monadic | dyadic |
|---|---|---|
⍴ |
reshape | |
, |
ravel | laminate and catenate |
⍪ |
table | catenate first |
⌽⍟ |
reverse | rotate |
⍉ |
transpose | |
↑ |
mix | take |
↓ |
split | drop |
∊ |
enlist | |
⊂ |
enclose | partitioned enclose |
⊆ |
nest | partition |
Examples
⊢m←2 2⍴1 2 3 4 ⍝ reshape
1 2
3 4
2 2 4⍴'ABCDEFGHIJKLMNOP'
ABCD
EFGH
IJKL
MNOP
,m ⍝ ravel
1 2 3 4
1 2 3,4 ⍝ catenate
1 2 3 4
1⌽1 2 3 4 ⍝ rotate
2 3 4 1
⌽m ⍝ reverse
2 1
4 3
⊖m ⍝ reverse first
3 4
1 2
⍉m ⍝ transpose
1 3
2 4
↑(1 2 3)(4) ⍝ mix
1 2 3
4 0 0
↓2 4⍴'COWSHENS' ⍝ split
┌────┬────┐
│COWS│HENS│
└────┴────┘
[ 1 2 3 ⋄ (4 5) 6 (7 8 9)]
┌───┬─┬─────┐
│1 │2│3 │
├───┼─┼─────┤
│4 5│6│7 8 9│
└───┴─┴─────┘
∊[ 1 2 3 ⋄ (4 5) 6 (7 8 9)] ⍝ enlist
1 2 3 4 5 6 7 8 9
≢⎕←⊂1 2 3 4 ⍝ enclose
┌───────┐
│1 2 3 4│
└───────┘
1
2 0 1 3 0 2 0 1⊂'abcdefg' ⍝ partitioned enclose
┌┬──┬─┬┬┬──┬┬──┬┐
││ab│c│││de││fg││
└┴──┴─┴┴┴──┴┴──┴┘
1 1 2 2 2⊆1 2 3 4 5 ⍝ partition
┌───┬─────┐
│1 2│3 4 5│
└───┴─────┘