Python3

Question 1

How to compare floating point values in python3?

Answer 1

python3: use math.isclose() to compare floating point values

The function is part of the math module and is available from Python 3.5 onward.
Useful for comparing floating-point numbers where exact equality is unreliable due to rounding errors.

Numbers close within default tolerance
print(math.isclose(1.000000001, 1.0)) # True

Numbers not close within default tolerance
print(math.isclose(1.0001, 1.0)) # False

Question 2

math.isclose()

python3

Answer 2

python3: use math.isclose() to compare floating point values

Question 3

What are 2 things to pay attention to when building a class in python?

Answer 3

1. the first parameter of all instance methods must be self
   def __init__(self, parameter)
2. when calling methods or attributes within the class, always need self.attributeName or self.method( parameters)

Question 4

How to generate random integers in [1, 2]
python3

Answer 4

import random
random.randint(1,2)

Question 5

What does this python3 code do?

import random
random.randint(1,2)

Answer 5

It generates random integers within [1, 2]

Question 6

In Python3, how to randomly choose a value from a list?

Answer 6

import random
myList = [1,2,3,4,5]
random.choice(myList)

Question 7

In Python3, how to set positive and negative infinitive?

Answer 7

float(‘inf’)
float(‘-inf’)

Question 8

What does this code print out?

for value in (1,10):
  print(value)

Answer 8

1
10

(1, 10) is a tuple, it iterates through each value in the tuple

Question 9

What does this code do?

y_set = 

sorted(

set( [ value for _, y, l in squares 

for value in (y, y + l)]))

Answer 9

the second for loop is wrapped inside the first for loop
the inner loops make use of the variables of the outer loops
value belongs to the innermost loop

How It Works:
1. Iterate through each square → for _, y, l in squares
2. Extract both y and y + l → for value in (y, y + l)
3. Store them in a list → [value for _, y, l in squares for value in (y, y + l)]
4. Convert to a set → set(…) removes duplicates.
5. Sort the set → sorted(…) returns a sorted list.

Question 10

y_values = sorted[set(value for _, y, l in squares for value in (y, y + l))]

what’s wrong with this code？

Answer 10

y_values = sorted（set(value for _, y, l in squares for value in (y, y + l))] ）

it supposed to use parentheses for sorted( )