辅导COMP9313留学生、cs/os辅导、 辅导讲解OS/CS、辅导国外英文OS/CS报告

日期：2018-09-26 10:22

COMP9313 2018s2 Project 2 (25 marks)

Problem 1 (13 pts):

Given a corpus of documents, compute the relative frequency f(wj|wi), i.e.,

Here, N(., .) indicates the number of times a particular co-occurring term

pair is observed in the corpus. In this problem, we consider that ???? and ????

co-occur if ???? appears after ????

in the same line.

Input:

The format of input files is like “pg100.txt”. For example, the input could be:

The Works of Shakespeare, by William Shakespeare

Language: English

Output:

Please get the terms from the documents as below:

? Ignore the letter case, i.e., convert all words to lower case first.

? Ignore terms starting with non-alphabetical characters, i.e., only

consider terms starting with “a” to “z”.

? Use the following split function to split the documents into terms:

split("[\\s*$&#/\"'\\,.:;?!\\[\\](){}<>~\\-_]+")

Each line of the output file is in format of “???? ???? ??(????

|????)”. The results are

sorted by the first term (i.e., ????

) in ascending order (alphabetical), then

sorted by the relative frequency (i.e., ??(????

|????)) in descending order, and

finally sorted by the second term in ascending order. The relative frequency

is of double precision. Given the above example, the output file is like:

by shakespeare 0.5

by william 0.5

language english 1.0

of shakespeare 0.5

of by 0.25

of william 0.25

shakespeare by 0.3333333333333333

shakespeare shakespeare 0.3333333333333333

shakespeare william 0.3333333333333333

the shakespeare 0.3333333333333333

the by 0.16666666666666666

the of 0.16666666666666666

the william 0.16666666666666666

the works 0.16666666666666666

william shakespeare 1.0

works shakespeare 0.4

works by 0.2

works of 0.2

works william 0.2

Code format:

Name your package as “comp9313.proj2”, your scala file as

“Problem1.scala”, and the object as “Problem1”. Store the final result in a

text file on disk. Your program should take two parameters: the input text

file and the output folder.

Problem 2 (12 pts, use the GraphX pregel operator):

Given a directed graph and a number k, compute the number of cycles with

length k. A cycle is a path with the same source and target node, and it does

not contain smaller cycles. For example, in the below graph, 0->1->3->4->0

is a cycle with length 4, but 2->3->4->3->2 is not a cycle with length 4,

since 2->3->2 and 3->4->3 are also cycles in the path.

Input:

Each line is in format of “EdgeId FromNodeId ToNodeId”. Given the left

graph, the input file is like below.

0 0 1

1 0 2

2 1 2

3 1 3

4 2 3

5 2 4

6 3 2

7 3 4

8 4 0

9 4 3

Output:

Show the number of cycles with length k. For example, given the sample

tiny graph and 4, the result is 3: 0->1->3->4->0, 0->1->2->4->0, and 0->2-

>3->4->0. Note that 0->1->3->4->0 and 1->3->4->0->1 are the same cycle,

and they only contribute 1 to the count.

Code format:

Name your package as “comp9313.proj2”, your scala file as

“Problem2.scala”, and the object as “Problem2”. Your program should take

two parameters: a file containing the graph and a value for k. Print the result

to stdout (i.e., using println()).

Documentation and code readability

Your source code will be inspected and marked based on readability and

ease of understanding. The documentation (comments of the codes) in your

source code is also important. Below is an indicative marking scheme:

Result correctness: 90%

Code structure, Readability, and

Documentation: 10%

Submission:

Deadline: Sunday 30th Sep 10:59:59 PM

Log in any CSE server (e.g., williams or wagner), and use the give

command below to submit your solutions:

$ give cs9313 project2 Problem1.scala Problem2.scala

Or you can submit through:

https://cgi.cse.unsw.edu.au/~give/Student/give.php

If you submit your assignment more than once, the last submission will

replace the previous one. To prove successful submission, please take a

screenshot as assignment submission instructions show and keep it by

yourself.

Late submission penalty

10% reduction of your marks for the 1st day, 30% reduction/day for the

following days.

Plagiarism:

The work you submit must be your own work. Submission of work partially

or completely derived from any other person or jointly written with any

other person is not permitted. The penalties for such an offence may include

negative marks, automatic failure of the course and possibly other academic

discipline. Assignment submissions will be examined manually.

Relevant scholarship authorities will be informed if students holding

scholarships are involved in an incident of plagiarism or other misconduct.

Do not provide or show your assignment work to any other person - apart

from the teaching staff of this subject. If you knowingly provide or show

your assignment work to another person for any reason, and work derived

from it is submitted you may be penalized, even if the work was submitted

without your knowledge or consent.