Get the intersection of list of array

https://docs.appian.com/suite/help/22.3/fnc_set_intersection.html

Hi Stefan,

I have tried intersection with reduce function but not able to achieve it as list of number array generate at runtime and I am not able to pass it like an arguments.

[{1,2,3},{2,3,4},{4,5,6}]

Thanks 

Manish

Why do you need reduce to do that?

intersection({1,2,3,4},{2,3,4},{4,5,6})

returns 4, which is the only number present in all the arrays.

The list of Array generates at run time , How will I pass the list of array to intersection function ? , So I tried to used the reduce function to send the result of intersection  for next iteration(interaction).

Manish_Kumar said:

generates at run time

Can you clarify what you mean by this?  What's the underlying code here?

a!localVariables(
  local!arrays: a!forEach(
    items: enumerate(1 + rand() * 10),
    expression: a!map(
      list: 1 + enumerate(rand() * 10)
    )
  ),
  reduce(
    rule!SSH_Intersect(a:_, b:_),
    local!arrays[1],
    ldrop(local!arrays, 1)
  )
)

rule!SSH_Intersect(a (map), b(map))
a!map(
  list: intersection(ri!a.list, ri!b.list)
)

Using just arrays does not work. I assume there is some undefined/weird behaviour inside reduce when feeding it with lists of lists.

a!localVariables(
  local!arrays: a!forEach(
    items: enumerate(1 + rand() * 10),
    expression: a!map(
      list: 1 + enumerate(rand() * 10)
    )
  ),
  reduce(
    rule!SSH_Intersect(a:_, b:_),
    local!arrays[1],
    ldrop(local!arrays, 1)
  )
)

rule!SSH_Intersect(a (map), b(map))
a!map(
  list: intersection(ri!a.list, ri!b.list)
)

Using just arrays does not work. I assume there is some undefined/weird behaviour inside reduce when feeding it with lists of lists.

Unknown said:

lists of lists

come on - you should already know that appian almost completely refuses to nicely handle lists-of-lists in the first place ;-)

True, still hoping .... The weird thing is, that, using just lists, it works sometimes, and sometimes it throws a weird error message.

Thanks everyone for your inputs.

Could you let me know how you have addressed this issue, as we are also facing the same issue

Did you try the solution I posted?

Ohh yes its working thank you.