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Head {.  _ 1 _ Take

{.y selects the leading item of y , or an item of fills if y has no items; that is, {.y 0{1{.y . Thus:
   a=: i. 3 2 3
   a;({.a);({."2 a);({."1 a)
+--------+-----+--------+-----+
| 0  1  2|0 1 2| 0  1  2| 0  3|
| 3  4  5|3 4 5| 6  7  8| 6  9|
|        |     |12 13 14|12 15|
| 6  7  8|     |        |     |
| 9 10 11|     |        |     |
|        |     |        |     |
|12 13 14|     |        |     |
|15 16 17|     |        |     |
+--------+-----+--------+-----+

   ]b=: ;/a
+-----+-------+--------+
|0 1 2|6  7  8|12 13 14|
|3 4 5|9 10 11|15 16 17|
+-----+-------+--------+
    
   {.&> b
 0  1  2
 6  7  8
12 13 14

   {. i.0 3
0 0 0
  If x is an atom, x{.y takes from y an interval of |x items; beginning at the front if x is positive, ending at the tail if it is negative.

In an overtake (in which the number to be taken exceeds the number of items), extra items consist of fills; zeros if y is numeric, a: if it is boxed, spaces if literal, and s: ' ' if symbol. The fill atom f is also specified by fit, as in {.!.f .

In general, if y is not an atom, x may be a list of length not more than $$y , and if y is an atom, it is replaced by ((#x)$1)$y . Element k produces (k{x){."(($$y)-k) y ; an infinite value is replaced by the length of the corresponding axis.
 

The following examples illustrate the use of the dyad take:
   y=: i. 3 4
   y;(2{.y);(5{.y);(_5{.y);(_6{.'abcd');(2 _3{.y)
+---------+-------+---------+---------+------+-----+
|0 1  2  3|0 1 2 3|0 1  2  3|0 0  0  0|  abcd|1 2 3|
|4 5  6  7|4 5 6 7|4 5  6  7|0 0  0  0|      |5 6 7|
|8 9 10 11|       |8 9 10 11|0 1  2  3|      |     |
|         |       |0 0  0  0|4 5  6  7|      |     |
|         |       |0 0  0  0|8 9 10 11|      |     |
+---------+-------+---------+---------+------+-----+

   2 {."1 y
0 1
4 5
8 9
  
   _ 2 {. y
0 1
4 5
8 9

   6{.'ab';'cde';'fghi'
+--+---+----++++
|ab|cde|fghi||||
+--+---+----++++


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