Difference between P() and E() function?

[#1]

Please any body help me what is difference between P&E function with example.

[marcus_malinow]

These are not functions, rather they are indirect set modifiers.

You may want to show total sales for customers who bought product A.

Sum({$<Customer=P({1<Product={'A'})>} Sales)

Or Sales for customers who haven't bought product A

Sum({$<Customer=E({1<Product={'A'})>} Sales)

[marcus_malinow]

Just to clarify, P means Possible, and E means Excluded

[maxgro]

some answers for the same question

P() &amp; E()

http://community.qlik.com/search.jspa?q=P+E

[SelvaKumar]

So,

Sum({$<Customer=E({1<Product={'A'})>} Sales)

equals to

Sum({$<Customer-=P({1<Product={'A'})>} Sales) ?

Kindly educate me  on this whether both are same or otherwise.

Thanks,

Selva