Homework 0

The goal of this homework is to practice the skills learned in Lecture 2. These skills will be essential for the rest of this course.

Before starting to work on this homework, make a new folder named submissions under spring-2015-homeworks\, copy the directory Homework-0\ in it and edit that copy.

Let's make sure that you placed everything in the correct folder



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import os
error = False

if os.path.basename(os.path.realpath('.')) != "Homework-0":
    print "The name of the current directory should be 'Homework-0'"
    error = True
    
if os.path.basename(os.path.realpath('..')) != "submissions":
    print "You should be working in the folder 'submissions'"
    error = True
    
if os.path.basename(os.path.realpath('../..')) != 'spring-2015-homeworks':
    print "You copied the directory under the wrong folder. It should be under 'spring-2015-homeworks'"
    error = True

if not error:
    print "You did everything correctly. Congrats!"

Now, assuming that everything is in their correct place, you should git add all the new directories/files and make your initial git commit.

This is a Markdown cell



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# Insert and edit your own markdown cell *below*. Write your favorite quote



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# This is a code cell. Try executing it.
print "hi"

Write a function that takes as argument a string and returns its 3-letter suffix. If the string is shorter than 3 letters, return the whole string



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def suffix_3(string):
    """
    Returns the 3-letter suffix.
    
    Parameters:
        string: str
    
    Returns:
        suffix: str
        If `string` is more than 3-letters long, `suffix` is its 3-letter suffix. Otherwise, `suffix` is the same as `string`.
    """



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print suffix_3("Hi!")
print suffix_3("Superb")

When you finish with the above function, don't forget to add and commit to your local git repository.

Let's print the versions of some packages that we will be using in the future. If any of these packages are not present, you should conda install them later.



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import numpy
print 'numpy:', numpy.__version__

import scipy
print 'scipy:', scipy.__version__

import matplotlib
print 'matplotlib:', matplotlib.__version__

import sklearn
print 'scikit-learn:', sklearn.__version__

import pandas
print 'pandas:', pandas.__version__

Submitting

Now, you can follow the submission guidelines from the lecture notes to push your changes to your Github fork.



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# Code for setting the style of the notebook
from IPython.core.display import HTML
def css_styling():
    styles = open("../../theme/custom.css", "r").read()
    return HTML(styles)
css_styling()