Difference between revisions of "Over"

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== Explanation ==
 
== Explanation ==
When the resulting function is used [[monadic]]ally, it has the same behaviour as if the [[Beside]] or [[Atop operator]] had been used:
+
When the resulting function is used [[monadic]]ally, it has the same behaviour as if the [[Beside]] or [[Atop (operator)|Atop]] operator had been used:
 
{|
 
{|
 
|<source lang=apl>  (g ⍥ h) ⍵</source>|| {{←→}} ||<source lang=apl>g (h ⍵)</source>
 
|<source lang=apl>  (g ⍥ h) ⍵</source>|| {{←→}} ||<source lang=apl>g (h ⍵)</source>

Latest revision as of 08:41, 22 November 2021

Over () is a primitive dyadic operator which takes two function operands and produces a derived function which pre-processes the argument(s) using the monadic right operand, before applying the left operand on/between the result(s).

Explanation

When the resulting function is used monadically, it has the same behaviour as if the Beside or Atop operator had been used:

  (g  h) 
g (h )

When the resulting function is used dyadically, both arguments are pre-processed:

 (g  h) 
(h ) g (h )

Examples

      x3 1 2
      y4 6 5
      x +(/) y ⍝ add the max of x and max of y
9
      ⍝ same as
      (/x)+⌈/y
9

External links

Lessons

Documentation

APL built-ins [edit]
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