DataSet Class

dataset.py: 23 points

Objective

In this section you’ll build the DataSet class that we’ll use to hold the data that our sorting algorithms will sort. The data itself will just be a list of integers (at least for this exercise), but having our own class lets us add some methods that will come in handy later.

How to Complete This Section

  • First, read over the DataSet Class Summary below to get a high-level view of how it works.
  • Next, read carefully through the Detailed Description of Methods and implement each method according to the specifications provided.

Tip: Don’t forget your docstrings!

Writing proper documentation is an important part of writing code (and, therefore, also part of your grade for this assignment). Remember to fill out the docstring for each method you implement. A useful docstring will have at least the following components:

  • A short summary explaining what the method does.
  • A list of parameters it accepts (other than self), including their data type and purpose.
  • A description of the method’s return value, if it has one.

DataSet Class Summary

Attributes

  • size (int): The total number of values in the dataset.
  • minimum (int): The lowest value in the dataset.
  • maximum (int): The highest value in the dataset.
  • data (list): A list containing the values themselves.

Methods

  • __init__
  • populate_data
  • get_data
  • set_data
  • is_sorted
  • display
  • __str__

Detailed Description of Methods

This section contains the requirements for each method your DataSet class will need to include, as well as some implementation suggestions.

__init__(self, size, minimum, maximum)

Initialize all of the attributes to the appropriate values. To accomplish this, you’ll need to do two things:

  1. Assign the parameters to object attributes.
  2. Call the populate_data method to initialize the data attribute (see description below).

populate_data(self)

Initialize self.data by assigning it to a list of random integers with length equal to self.size. This method will generate the list so the integers in it are chosen at random but are all greater than or equal to self.minimum and less than or equal to self.maximum. Note that it’s OK if some values appear more than once.

get_data(self)

Returns the list self.data.

set_data(self, new_data)

Accepts a list of integers and assigns it to the attribute self.data, replacing the random values generated by default. Although we will primarily want to use the randomly generated values, this method is convenient for testing that the object and our sorting methods are functioning as expected.

In order to make sure our object is internally consistent, this method will also need to update the size, minimum and maximum attributes to reflect the relevant characteristics of the new data attribute. For example, if the new value of self.data is [0, 3, 10], this method should update self.size to 3, self.minimum to 0, and self.maximum to 10.

is_sorted(self)

Checks whether self.data is sorted from lowest to highest and returns True if it is, False otherwise.

display(self)

This method has been implemented for you, but requires you to complete the __str__ method below. When the __str__ method is completed correctly, display will print a tab-delimited representation of the dataset to the terminal and pause until the user hits the Return key.

__str__(self)

Returns a string containing all the values in the dataset, separated by tabs (\t). Python uses this method whenever a program prints a DataSet object.

Testing

The test_dataset_class() function is intended to run a number of quick consistency checks to make sure the methods of the DataSet class are functioning correctly. When the DataSet class and the test function are complete, running python3 dataset.py should produce output similar to the example below (some of the actual values will differ since they are generated at random). Note that it will pause after each call to the display method and you will have to hit the Return key to advance the program.

*******************************************************************************
Testing __init__, populate_data, and get_data.
-------------------------------------------------------------------------------
Creating dataset object with 10 values between 0 and 10.
The generated values are:
[8, 5, 5, 5, 7, 8, 4, 9, 1, 6]
*******************************************************************************
Testing display and __str__.
-------------------------------------------------------------------------------
8	5	5	5	7	8	4	9	1	6	

*******************************************************************************
Testing set_data.
-------------------------------------------------------------------------------
Setting data to [4,1,9]
Display new data:
4	1	9	

*******************************************************************************
Testing is_sorted.
-------------------------------------------------------------------------------
Sorted: False
Setting data to [1,2,3,4]
Sorted: True

Note on Evaluation

Your grade on this section is based on how well you implement the requirements listed above. Here are a few things you’ll want to double check:

  • Does your class have all the attributes and methods described?
  • Do your attributes and methods work as specified?
  • Have you included useful docstrings for all of your methods?