Set Intersection with exclusion

[mloy3]

Work Unit ID	Task ID
A	1
A	2
A	3
B	1
B	3
B	4
C	2
C	3
C	4
D	1

Hi! I been cranking my head for the past few hours in trying to get to the results but to no avail. I am trying to count the instances whereby a work unit id has been associated with Task id 1, but 2 is not associated.

In the table above I would need 2 results, 1 for B and D each. 
Tried this but didnt work:
count({<[Work Unit ID]=P({<Task ID={1}>}[Work Unit ID])>*<[Work Unit ID]=E({<Task ID={2}>}[Work Unit ID])>}Work Unit ID)

[jonathandienst]

You are missing some square brackets:

Count({
	<[Work Unit ID]=P({<[Task ID]={1}>} [Work Unit ID])>*
	<[Work Unit ID]=E({<[Task ID]={2}>} [Work Unit ID])>
    }
[Work Unit ID])

[Vegar · Accepted solution]

You missed out some parantheses/brackets [] and a distinct

=count({<[Work Unit ID]=P({<[Task ID]={1}>}[Work Unit ID])> * <[Work Unit ID]=E({<[Task ID]={2}>}[Work Unit ID])>} DISTINCT[Work Unit ID])

[mloy3]

Hi Jontydkpi, thanks for the quick reply. Even after adding [] to all the Task ID and Work Unit ID, i find this formula to yield 0 result. 

[Vegar]

Try this script:

LOAD * inline [
Work Unit ID,Task ID
A,1
A,2
A,3
B,1
B,3
B,4
C,2
C,3
C,4
D,1];

Using the two expressions by @jonathandienst  and me will result in this table-.

[mloy3]

Thank you for your help Jontydkpi. I finally realized why it is not working! your formula is indeed correct

[mloy3]

Thanks for your help Vegar! This is working as intended. i realized the mistake and added the DISTINCT