sdd help required for evolution of prog languages (1 Viewer)

[xlr9]

sdd help needed (via forum OR tutoring arrangement)

can any1 possible help me out here. I particularly need some help understanding some of the content (particularly algorithms) in "evolution proprogramming languages". my teacher chose the teach the other option topic (but i hate it) and i need some quality tuition to bring me up to speed. i live on the south coast, but i'll be in syd for a few days kinda soon.... if i could meet up with some1 that can talk me thru the option topic stuff, i'd be happy 2 pay etc

please keep this thread in the sdd forum. sdd tutoring is a niche area and the thread wont get the required views in the buy/sell tuition forum

 

[Winston]

hmmm... i dont find being tutored for 1/2 theory subject is worth it, u can study on ur own and ask people on the forums, if u want u can add me to MSN, and bother me, i wouldnt mind...

 

[sunny]

Aren't you class of 2003 though xlr9?

 

[xlr9]

I ended up doing pathways (hsc over 2 years)

 

[hornetfig]

well it's not as though any of the teachers could have taught you Evolution either - just read the content of the three texts (Heinmann, PDC, Excel)

 

[xlr9]

well it's not as though any of the teachers could have taught you Evolution either - just read the content of the three texts (Heinmann, PDC, Excel)

thanks for the advice. I have read through all the texts and understand each of the concepts (paradaigms, inheritance etc etc) but I don't understand algorithms (in the evolution chapter). I think what i really need is some hands on tuition with some1 who knows what they're talking about (ie NOT my teacher )

 

[funniboi]

Try the Buy/Sell Tutition section in the General Forum.

 

[xlr9]

Try the Buy/Sell Tutition section in the General Forum.

dang! can a mod plz move this back to the software design forum. it isn't going to get enough coverage here. sdd tuition is a pretty niche area. thx

 

[xlr9]

does ne1 have the solutions 2 the indep trial (esp Q24b). This is the kinda stuff im having trouble with:

 

[artfaggette]

does ne1 have the solutions 2 the indep trial (esp Q24b). This is the kinda stuff im having trouble with:

I second this request, I'm completely stuck, as is my teacher, my friends and the remainder of the class.

Thankee

 

[sunny]

I will do the first two, see if it helps.

i) Identify the paradigm supported by the above programming language. Justify your response

I would say this is a functional language. It has features of a functional paradigm
1) There are only functions
2) It uses recursion
3) There are no variables
4) Values in the parameters do not change

ii) Describe the processing that occurs during the evaluation of the expression (this 4)

I will re-write the code here to make it more readable:

this n
  if n = 0
    return 0
  else
    return n + this(n-1)

f1 a b
  if b > a
    return 0
  else
    return b + f1(a,b++)

that n
  f1 n 1

If you call (this 4)
this will execute, where n = 4.

This sequence of steps would follow:

this 4
return (4 + this 3)
return (4 + return 3 + this 2)
return (4 + return 3 + return 2 + this 1)
return (4 + return 3 + return 2 + return 1 + this 0)
return (4 + return 3 + return 2 + return 1 + return 0)

Therefore, this 4 calculates 4+3+2+1+0.

 

[xlr9]

i have the official solutions. (although i dont understand them) will post them 2nite

 

[artfaggette]

Much appreciated. It actually makes sense now!
Thankyou so much sunny and also xlr9 (in advance).

 

[xlr9]

24b

here is the official answers (typed out) for indep 24b. I still don't totally understand parts i/ii/iii/iv. If some1 could please shed some light I'm sure we would all be very greatful.

http://port80.fastmail.fm/24b.html

edited: changed URL

 

[sunny]

here is the official answers (typed out) for indep 24b. I still don't totally understand parts i/ii/iii/iv. If some1 could please shed some light I'm sure we would all be very greatful.

http://www.vbux.com/24b.html

What don't you understand about i and ii? If you have a good understanding of the different paradigms, you should be able to answer part i fairly easily.

As for part ii, try and follow what I have written above. The first time this 4 is executed, it will perform:
4 + this 3

When you execute this 3, it will perform:
3 + this 2

This brings the current solution to 4 + (3 + this 2)

Then this 2 executes........and so on, until this 0 is called, at which point this returns 0 instead of calling this again.

This particular behaviour of a functional repetitively invoking itself (this calling this calling this....) is called recursion. Although recursion can also be done in other paradigms, it is a distinct feature in functional languages, in that it relies on recursion to work properly.