>
> In fact, I think it would be a fruitful discussion to compare and contrast
> the cases where we use:
>
> * "
> * /
> * ^:iteration_calculator
> * ^:condition^:_
> * $:
> * for. and while.
>
> I say that because I struggled with the third sentence of this message. I
> couldn't quite articulate the type of problem which would cause one to use
> $: instead of ^: .
>
> -Dan
I myself am far too incompetent to start this fruitful discussion, but
actually I do have several peaces of code which are implemented with for or
while loops. I don't like them and I'm quite sure there are nicer ways to
write them, but it has been to complicated to me so far.
For example the following peace:
y is a matrix of shape n * n
x is a number between 0..n-1
roll =. ?+/ row =. x { y
index =. 0
while. roll > 0 do.
roll. =. roll. - index { row
index =: >: index
end.
if. index = 0 do.
index =. 1
end.
For the last if-clause I figured out something like this:
check =: =&0^:(=&0)
And 'check index' seems to work as expected, but I'm not quite sure if it
really is working correctly
Kairit Sirts
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