python-functions.ipynb

Kernel: Python 3

Practice Python Functions

_Author: Ryan Dunlap (San Francisco)

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Resources: Potentially Helpful Functions

• Dictionary Comprehension

• Enumerate

• Length

• Int

• List

Nowadays, most of the string module's components are already built into Python. However, it still has several constant values that can be useful, including:

string.ascii_uppercase

import string

string.ascii_uppercase

'ABCDEFGHIJKLMNOPQRSTUVWXYZ'

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1) Write a function that takes the length of a side of a square as an argument and returns the area of the square.

# A:
def square(x):
    return x**2 

square(2)

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2) Write a function that takes the height and width of a triangle and returns the area.

# A:
def triangle(x,y):
    return x*y*(1/2)  #height x width divided by 2, to get area of triangle

triangle(2,4)

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3) Write a function that takes a string as an argument and returns a tuple consisting of two elements:

• A list of all of the characters in the string.

• A count of the number of characters in the string.

# A:
my_string = 'hello world'
def tupe (x):
    return (set(x), len(x)) #set gives you unique variables

_, result = tupe(my_string)

result

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4) Write a function that takes two integers, passed as strings, and returns the sum, difference, and product as a tuple (with all values as integers).

# A:
def sum_two(x, y):
    x = int(x)
    y = int(y)
    return(x+y, x-y, x*y)
sum_two('3', '4')

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5) Write a function that takes a list as the argument and returns a tuple consisting of two elements:

• A list with the items in reverse order.

• A list of the items in the original list that have an odd index.

# A:
def funny_func(x):
    return(x[::-1], x[::2]) #from, to, step 
    
    
funny_func('hello world')

def list_manip(x):
    x_reverse = x[::-1]
    
    odd_index = []
    for number, i in enumerate(x):
        if number %2 ==1:
            odd_index.append(x)
            
            
            
list_manip('hello world')      

for i, v in enumerate(['a', 'b', 'c']):
    print(i, v)

def list_manipulation(l):
    l_reversed = l[::-1]
    
    odd_index = []
    for number, i in enumerate(l):
        if number %2 ==1:
            odd_index.append(i)
    
    ## alt: l[1::2] 
        
    return l_reversed, odd_index

    # return l[::-1], l[1::2] one liner


list_manipulation([1,2,3,4])

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Challenge: Write a function that returns the score for a word. A word's score is the sum of the scores of its letters. Each letter's score is equal to its position in the alphabet.

So, for example:

• A = 1, B = 2, C = 3, D = 4, E = 5

• abe = 8 = (1 + 2 + 5)

Hint: The string library has a property ascii_lowercase that can save some typing here.

# A:
def word_score(input_string):
    string_lower = input_string.lower()
    
    values_dict = dict(zip(string.ascii_lowercase, range(1,27)))
    
    score = 0 
    for letter in string_lower:
        score += values_dict[letter]
    
    return score

word_score('data')

# A:
def score(word):
    total = 0
    word = word.lower()
    for letter in word:
        total += (list(string.ascii_lowercase).index(letter)+1)
    return total

score('hello')