I have checked everywhere and I can't seem to locate the problem. The compiler is giving me this error: "error FS0039: The value or constructor 'dotProduct' is not defined
". But dotProduct is currently defined.
Visual Studio 2010 is also highlighting the second let (let rec dotProductAux list1 list2 acum =
) saying that the expression is unfinished.
let dotProduct list1 list2 =
let rec dotProductAux list1 list2 acum =
match list1 ,list2 with
| [],l | l,[] -> acum
| head1 :: tail1, head2 :: tail2 -> let updated = (head1 * head2) + acum
开发者_高级运维 (dotProductAux tail1 tail2 updated)
This code multiplies and adds two list like this:
dotProduct [1;4;7] [3;4;1];; //(1*3) + (4*4) + (7*1)
I'm fairly new to F# and can't seem to get this code right. Any help?
The body of dotProduct
contains the definition of dotProductAux
, but no actual expression. You need to actually call dotProductAux
(i.e. you're missing the call dotProductAux list1 list2 0
after the let rec
).
Furthermore the case (Apparently you've already fixed this in an edit).| [],[]| l,[] -> accum
will cause an error because the second pattern binds the variable l
, while the first does not. You can fix that by replacing l
with _
, since you don't actually need it.
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