[Jprogramming] learning: Having trouble writing loopless scripts

[Ian Gorse]

Thanks to everyone that replied, although I am not comfortable at reading
Raul Miller's solution, I am still interested in other ways to solve my
problem.
I have only scratched the surface with hooks and forks , as I found them
quite difficult to understand on my first read through.

My actual problem is slightly more complicated than my original post, but I
wanted to simplify it to understand it better.

If I was to extend it slightly, I have this

c=: 4 : '(!(x+y)) % (x+y)'
a=: 1 2 3 4 5

and the result I want are
   a c 1
1 2 6 24 120
   a c 2
2 6 24 120 720
   a c 3
6 24 120 720 5040

To do this without a loop, I came up with this
b=: 1 2 3

NB. First Approach
a c b
|length error: c
|   (!(x+y))%(x    +y)

One might think so but this is not true.
> "/" itself is not causing an "each on each".


Thank you for explaining that as my second approach went something like this

NB. Second Approach
a c/ b
|length error: c
|   (!(x+y))%(x    +y)

Finally I simplified 'c' a section at a time until I came up with
c2=: 4 : '(!(a+/b)) % (a+/b)'

NB. Third Approach
a c2 b
  1   2    6
  2   6   24
  6  24  120
 24 120  720
120 720 5040