I'd like to add all items in a vector in Scheme.

I believe my problem areas are in the way I use lambda (very unsure of this expression's correct usage), assign the length of the vector to variable i and add the value I attempt to get from each of the elements in the vector. Not sure how to fix the error based on the error message.

The error I am getting is just:

#< procedure>

the code:

(define (sum X)
   (define length (vector-length X)) ;potential problem area
       (lambda (length)
       (lambda (total)
          (do (
              (i length (- i 1))
              (a (vector-ref X i)(+ a total)) ; potential problem area
              )
           ((zero? i) total)
            )
         )
         )
  )

Revised code (thanks user479988) - I've removed the lambdas, realized I dont need them. And defined the variable i to an initial 0.

The error is now the output is showing 0.

The code:

(define (sum X)
  (define length (vector-length X)) ;potential problem area
  (define total 0)
  (define i 0)
  (do (
       (i length (- i开发者_Go百科 1))
       (a (vector-ref X i)(+ a total)) ; potential problem area
       ((zero? i) total)
       )
    )
  )

Could you please advise on the i) error ii) logic of the algorithm

Thanks!

I can't really tell the structure of your program because the parenthesis are mismatched and the indentation is hard to read but I think you're not giving the lambdas any input so instead of returning the sum, you return the function you made with the lambdas since you didn't evaluate them.