# Atop (operator)

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Atop () is a primitive dyadic operator which takes two function operands and produces a derived function which uses the left operand monadically to post-processes the result of the ambivalent right operand.

## Explanation

When the resulting function is used monadically, it has the same behaviour as if the Atop 2-train or any of the Beside or Over operators had been used:

 (g ⍤ h) ⍵ ${\displaystyle \Leftrightarrow }$ g (h ⍵)

When the resulting function is used dyadically, the result is post-processed:

 ⍺ (g ⍤ h) ⍵ ${\displaystyle \Leftrightarrow }$ g ⍺ h ⍵)

## Examples

x3 1 2
y4 6 5
x - y ⍝ the negation of the max of x y
¯4 ¯6 ¯5
⍝ same as
-xy
¯4 ¯6 ¯5