Hi,
I think the problem is in the types.
If you look at the type of the function round, you can see its result is an Integral:

>> :t round
round :: (Integral b, RealFrac a) => a -> b

The result of the division x/y, instead, is a Fractional, and you cannot test equality between two things of different types.
To solve the problem you can do a type cast, by converting the Integral to a Num, using fromInteger:

(fromInteger (round (x/y))) == (x/y)

This should work.

Cheers,
Ut




Il giorno mer 8 gen 2020 alle ore 16:01 Alexander Chen <alexander@chenjia.nl> ha scritto:
hi,

for a List comprehension I want to only include the integers of a division. In my beginners mind this should work:

(round (x / y)) == (x / y)

however, i get a nontrivial error blurp.

what am i doing wrong?

best,

Alexander 



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