Meaning of life

[melsman]

We are not far from being able to execute the following one-liner - see http://aplwiki.com/FinnAplIdiomLibrary#Miscellaneous:

⍎⊖⍕⊃⊂|⌊-*+○⌈×÷!⌽⍉⌹~⍴⍋⍒,⍟?⍳0

We will not be able to support execute ⍎, box ⊂. So we should, with an implementation of ⌹ be able to compile the following expression:

⊖⍕⊃|⌊-*+○⌈×÷!⌽⍉⌹~⍴⍋⍒,⍟?⍳0

Here is how it looks with http://www.tryapl.org:

Comments:

• In the example, ⌹ is applied to the scalar 1.
• There is an issue with ⍳0; ⍳ is required to take an integer value - subtyping fix needed.
• We don't support '!'.

[athas]

Do you know of a good description of ⌹?

\ Troels /\ Henriksen

[melsman]

Dyadic: A ⌹ B = (⌹B)+.×A

Monadic: Matrix inverse (see http://dyalog.com/uploads/documents/MasteringDyalogAPL.pdf page 453)