reciprocal of a complex number

[giangiquario]

In Dyalog 13.0

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     ÷ .5E160J.5e160
DOMAIN ERROR
      ÷5E159J5E159
     ∧

I think that it is a overflow pitfall.

I suggest to change the implementation of "reciprocal" into the interpreter.
For example you could do something like :

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Reci←{
     ReIm←{9 11○⍵}⍵
     recip←{>/|⍵:{q←÷/⌽⍵ ⋄ 1(-q)÷+/⍵×1 q}⍵
         {q←÷/⍵ ⋄ q ¯1÷+/⍵×q 1}⍵}ReIm ⍝(avoiding overflow)
     {+/1 0J1×⍵}recip
 }

In fact:

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     Reci .5E160J.5e160
1E¯160J¯1E¯160

[Jay|Dyalog]

Well spotted! I have raised this as issue 7628.

A very simple work around is to use divide instead of reciprocal:

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      1÷.5E160J.5e160
1E¯160J¯1E¯160

Thanks,
Jay.