#!/usr/bin/env python # coding: utf-8 # # Set and Booleans # # There are two other object types in Python that we should quickly cover. Sets and Booleans. # # ##Sets # # Sets are an unordered collection of *unique* elements. We can construct them by using the set() function. Let's go ahead and make a set to see how it works # In[1]: x = set() # In[3]: # We add to sets with the add() method x.add(1) # In[4]: #Show x # Note the curly brackets. This does not indicate a dictionary! Although you can draw analogies as a set being a dictionary with only keys. # # We know that a set has only unique entries. So what happens when we try to add something that is already in a set? # In[5]: # Add a different element x.add(2) # In[6]: #Show x # In[7]: # Try to add the same element x.add(1) # In[9]: #Show x # Notice how it won't place another 1 there. That's because a set is only concerned with unique elements! We can cast a list with multiple repeat elements to a set to get the unique elements. For example: # In[10]: # Create a list with repeats l = [1,1,2,2,3,4,5,6,1,1] # In[12]: # Cast as set to get unique values set(l) # ## Booleans # # Python comes with Booleans (with predefined True and False displays that are basically just the integers 1 and 0). It also has a placeholder object called None. Let's walk through a few quick examples of Booleans (we will dive deeper into them later in this course). # In[13]: # Set object to be a boolean a = True # In[16]: #Show a # We can also use comparison operators to create booleans. We will go over all the comparison operators later on in the course. # In[17]: # Output is boolean 1 > 2 # We can use None as a placeholder for an object that we don't want to reassign yet: # In[18]: # None placeholder b = None # Thats it! You should now have a basic understanding of Python objects and data structure types. Next, go ahead and do the assessment test! # In[ ]: