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# Objects and Data Structures Assessment Test
Write a brief description of all the following Object Types and Data Structures we've learned about:
Numbers:
Strings:
Lists:
Tuples:
Dictionaries:
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10*10/1 + 2**2 - 3.75
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Explain what the cell below will produce and why. Can you change it so the answer is correct? It will produce 0.6666 because it is python 3 so will use real division
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2/3
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Answer these 3 questions without typing code. Then type code to check your answer.
What is the value of the expression 4 * (6 + 5)
44
What is the value of the expression 4 * 6 + 5
29
What is the value of the expression 4 + 6 * 5
34
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4 + 6 * 5
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What is the type of the result of the expression 3 + 1.5 + 4? It is a float because one of the number is a floating point
LaTex: a not sure how to get the
What would you use to find a number’s square root, as well as its square?
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print(2**2) # squared (raise to the power of 2)
print(2**0.5) # square root (raise to the power of 1/2)
Given the string 'hello' give an index command that returns 'e'. Use the code below:
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s = 'hello'
# Print out 'e' using indexing
# Code here
s[1]
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Reverse the string 'hello' using indexing:
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s ='hello'
# Reverse the string using indexing
print (s[::-1])
# Code here
Given the string hello, give two methods of producing the letter 'o' using indexing.
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s ='hello'
# Print out the
# Code here
print(s[-1])
print(s[4])
Build this list [0,0,0] two separate ways.
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l = [0,0,0]
print (l)
l = [0]*3
print(l)
l1 = list()
l1.append(0)
l1.append(0)
l1.append(0)
print(l1)
Reassign 'hello' in this nested list to say 'goodbye' item in this list:
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l = [1,2,[3,4,'hello']]
l1 = l[2]
l1[l1.index('hello')] = 'goodbye'
print(l)
Sort the list below:
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l = [5,3,4,6,1]
l.sort()
print(l)
l = [5,3,4,6,1]
print(sorted(l))
Using keys and indexing, grab the 'hello' from the following dictionaries:
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d = {'simple_key':'hello'}
# Grab 'hello'
print(d['simple_key'])
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d = {'k1':{'k2':'hello'}}
# Grab 'hello'
print(d['k1']['k2'])
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# Getting a little tricker
d = {'k1':[{'nest_key':['this is deep',['hello']]}]}
#Grab hello
print(d['k1'][0]['nest_key'][1][0])
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# This will be hard and annoying!
d = {'k1':[1,2,{'k2':['this is tricky',{'tough':[1,2,['hello']]}]}]}
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d = {'k1':[1,2,{'k2':['this is tricky',{'tough':[1,2,['hello']]}]}]}# print it all
print(d)
# get the set at 'k1'
my_set = d['k1']
print('my_set: ' + str(my_set))
# get the dictionary at index 2 of the set
my_dict = my_set[2]
print('my_dict: ' + str(my_dict))
my_set1 = my_dict['k2']
print ('my_set1: ' + str(my_set1))
my_dict2 = my_set1[1]
print ('my_dict2: ' + str(my_dict2))
my_set2 = my_dict2['tough']
print ('my_set2: ' + str(my_set2))
my_set3 = my_set2[2]
print('my_set3: ' + str(my_set3))
indx = my_set3.index('hello')
print('indx = ' + str(indx))
print(my_set3[indx])
print (d['k1'][2]['k2'][1]['tough'][2][0])
Can you sort a dictionary? Why or why not? you cant sort a dictionary because it is keys and values
What is the major difference between tuples and lists? tuples are immutable and lists are mutable
How do you create a tuple? with parentheses and a comma delimited list (1,2.3)
What is unique about a set? a set contains only unique items and is immutable
Use a set to find the unique values of the list below
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l = [1,2,2,33,4,4,11,22,3,3,2]
print (l)
s = set(l)
print (s)
For the following quiz questions, we will get a preview of comparison operators:
Operator | Description | Example |
---|---|---|
== | If the values of two operands are equal, then the condition becomes true. | (a == b) is not true. |
!= | If values of two operands are not equal, then condition becomes true. | |
<> | If values of two operands are not equal, then condition becomes true. | (a <> b) is true. This is similar to != operator. |
> | If the value of left operand is greater than the value of right operand, then condition becomes true. | (a > b) is not true. |
< | If the value of left operand is less than the value of right operand, then condition becomes true. | (a < b) is true. |
>= | If the value of left operand is greater than or equal to the value of right operand, then condition becomes true. | (a >= b) is not true. |
<= | If the value of left operand is less than or equal to the value of right operand, then condition becomes true. | (a <= b) is true. |
What will be the resulting Boolean of the following pieces of code (answer fist then check by typing it in!)
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# Answer before running cell
2 > 3
#false
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# Answer before running cell
3 <= 2
#false
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# Answer before running cell
3 == 2.0
#false
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# Answer before running cell
3.0 == 3
#true
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# Answer before running cell
4**0.5 != 2
#false
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Final Question: What is the boolean output of the cell block below?
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# two nested lists
l_one = [1,2,[3,4]]
l_two = [1,2,{'k1':4}]
#True or False?
#3>=4
#false
l_one[2][0] >= l_two[2]['k1']
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