Assignment No. 6 Programming Language Paradigms

Assignment No. 6
EECS 368
Programming Language Paradigms

Deliverables:
1. Copy of Rubric6.docx with your name and ID filled out (do not submit a PDF)
2. Haskell script file(s).
3. Screen print(s) as described below (Copy and paste the output to a Word
document and PDF it).
Assignment:
• In this assignment, you will define 5 Haskell functions.
• Each function description below shows an example of the function working.
• Once your code is working, show that the example works on your function with a
screen print.
• Also, show in a screen print how your function executes using a test case.
• You may put all of the functions in one script file or in separate script files.
• You may put the screen prints in one file or separate files.
• replicate function:
In a similar manner to the function length described in the “Haskell List
Comprehension” lecture, show how the library function: replicate :: Int -
> a -> [a], which produces a list of identical elements, can be defined
using list comprehension. For example:
> replicate 3 True
[True, True, True]
Show a screen print with your code using the following test case:
> replicate 5 “test code”
• perfects function:
A positive integer is perfect if it equals the sum of all of its factors,
excluding the number itself. Using a list comprehension, define a
function: perfects :: Int -> [Int] that returns the list of all perfect numbers
up to a given limit. For example:
> perfects 500
[6,28,496]
Show a screen print with your code of:
> perfects 9000
• find function:
Suppose that we represent a lookup table by a list of pairs of keys and
values. Then for any type of keys that supports equality, define a function
as follows: find :: Eq a => a -> [(a,b)] -> [b] that returns the list of all
values that are associated with a given key in a table. For example:
> find 'b' [('a',1),('b',2),('c',3),('b',4)]
[2,4]
Show a screen print with your code of:
> find 'c' [('a',1),('b',2),('c',3),('b',4),('c',25)]
• positions function:
Redefine the positions function from the “Haskell List Comprehension”
lecture using the find function. For example:
> positions 0 [1,0,0,1,0,1,1,0]
[1,2,4,7]
Show a screen print with your code using the following test case:
> positions 1 [1,0,0,1,0,1,1,0]
• scalarproduct function:
The scalar product of two lists of integers xs and ys of length n is given by
the sum of the products of the corresponding integers:
For example:
> scalarproduct [1,2,3] [4,5,6]
32
Using a list comprehension and the zip function, define a function that
returns the scalar product of two lists.
Show a screen print with your code using the following test case:
> scalarproduct [-1,2,3] [-4,-5,6]
• Feel free to use code you find on the Internet. Just be sure to include comments
that adequately describe the code.
• Provide comments for the Haskell code that explain what each line of code is
doing. See rubric below.

Rubric for Program Comments
Exceeds Expectations
(90-100%)
Meets Expectations
(80-89%)
Unsatisfactory
(0-79%)
Software is adequately
commented with prologue
comments, comments
summarizing major blocks of
code, and comments on every
line.
Prologue comments are present
but missing some items or some
major blocks of code are not
commented or there are
inadequate comments on each
line.
Prologue comments are missing
all together or there are no
comments on major blocks of
code or there are very few
comments on each line.
Adequate Prologue Comments:
• Name of program contained in the file (e.g., EECS 368 Assignment 6 - replicate)
• Brief description of the program, e.g.:
o Haskell function for replicate
• Inputs,e.g.,:
(xsi * ysi ∑ )
i = 0
n-1
o Number of replications
o Element to replicate
• Output, e.g.,
o List of replicated elements
• Author’s full name
• Creation date: The date you first create the file, i.e., the date you write this
comment
Adequate comments summarizing major blocks of code and comments on every line:
• Provide comments that explain what each line of code is doing.
• You may comment each line of code (e.g., using --) and/or provide a multi-line
comment (e.g., using {- and -}) that explains what a group of lines does.
• Multi-line comments should be detailed enough that it is clear what each line of
code is doing.
Remember:
• Your Programming Assignments are individual-effort.
• You can brainstorm with other students and help them work through problems in
their programs, but everyone should have their own unique assignment programs.