Re: [Bug-apl] A question.

[Elias Mårtenson]

I'll give it a shot:

      foo ← {⍺ ⍶ ⍵}

This defines foo as an operator that applies the function on its two arguments.

I.e. in the following example:

      10 +foo 20

30

The foo operator simply applies + to 10 and 20, returning 30. In other words, ⍶ is the function that goes to the left of the operator name.

Similarly, ⍹ is the function that goes on the right of the operator name:

      bar ← {(⍺ ⍶ 2) ⍹ (⍵ ⍶ 3) }

      10 +bar- 20

¯11

The call to bar results in the following formula being evaluated: (10+2)-(20+3).

Regards,

Elias

On 18 May 2016 at 10:48, Christian Robert <address@hidden> wrote:

Sorry, no explanations given.

      hook←{⍵⍶⍹⍵}
      +hook÷2
2.5
      hook←{⍵⍶⍹⍵⊣⎕←⍵⊣⎕←⍶⊣⎕←⍹⊣⎕←⍵}
      +hook÷2
2
DOMAIN ERROR
hook[1]  λ←⍵ ⍶ ⍹ ⍵⊣⎕←⍵⊣⎕←⍶⊣⎕←⍹⊣⎕←⍵
                             ^^
please explain the principle to a newbie.

I really want a working examples.


Xtian.

On 2016-05-17 22:30, Xiao-Yong Jin wrote:

They are for direct function (operator?) definitions.  Try:

      hook←{⍵⍶⍹⍵}
      +hook÷2
2.5

On May 17, 2016, at 8:24 PM, Christian Robert <address@hidden> wrote:

hi,

in the result of "]help" I can see:


     λ       { ... } result
     ⍺       { ... } left value argument
     ⍵       { ... } right value argument
     χ       { ... } axis argument
     ⍶       { ... } left function argument
     ⍹       { ... } right function argument


can someone explain to me the usage of ⍶ and ⍹
with some examples ?

I understant the first four, but not the last two.

many thanks,

Xtian.