First off: you’re very close. Thing two: I think you need a clearer comment on the meaning of the “months” vector. Your description does not actually say what the vector represents or contains.
Thing three: Here’s my question to you. Suppose that I tell you a year and a month and the result of (vector-ref months x). To be more concrete, suppose I tell you the year is 2234 and the month is 4 and the result of (vector-ref months x) is 30. How many days would that month have? Can you explain how to compute the answer for each of the test cases below? John Clements > On Apr 19, 2020, at 11:50, Suz Renae <[email protected]> wrote: > > I am new to racket (first year student) and since class has been pushed to > online only, I am having a harder time. > > We are currently working on vectors and hash tables. I feel like I keep > overthinking it and keep getting stuck. I know that the first parameter in > the function will be the year and the second will be the (vector-ref months > x)that I pull from the defined vector. > > The question I am having a hard time with and what I have actually done below. > > Create a function that calculates the number of days in a month given a year > and a month > • Call the function number-of-days-in-month, and it's signature is > number, number -> number > • Example: > (number-days-in-month 2016 1) -> 31 > (number-days-in-month 2016 11) -> 30 > (number-days-in-month 2016 12) -> 31 > (number-days-in-month 1900 2) -> 28 > (number-days-in-month 2000 2) -> 29 > (number-days-in-month 2016 2) -> 29 > (number-days-in-month 2200 2) -> 28 > What I have so far... > > ;Leap Year > (define (leap-year? year) > (and (zero? (modulo year 4)) > (or (not (zero? (modulo year 100))) > (zero? (modulo year 400)) > ) > ) > ) > > ;Months with days vector, beginning at an index of 0 since there is not 0th > month > (define months (vector 0 31 28 31 30 31 30 31 31 30 31 30 31)) > > (check-expect(number-days-in-month 2016 1)31) > (check-expect(number-days-in-month 2016 11)30) > (check-expect(number-days-in-month 2016 12)31) > (check-expect(number-days-in-month 1900 2)28) > (check-expect(number-days-in-month 2000 2)29) > (check-expect(number-days-in-month 2016 2)29) > (check-expect(number-days-in-month 2200 2)28) > > I need help with building the actual function and what conditionals I should > be using. > > (define (number-days-in month ?? ??) > (cond > [ > > -- > You received this message because you are subscribed to the Google Groups > "Racket Users" group. > To unsubscribe from this group and stop receiving emails from it, send an > email to [email protected]. > To view this discussion on the web visit > https://groups.google.com/d/msgid/racket-users/5d017eef-b235-4a8b-94fa-fe1e3f7b766e%40googlegroups.com. -- You received this message because you are subscribed to the Google Groups "Racket Users" group. To unsubscribe from this group and stop receiving emails from it, send an email to [email protected]. To view this discussion on the web visit https://groups.google.com/d/msgid/racket-users/02cda61a-5bea-4087-8518-e4a44d4dfa56%40mtasv.net.
