Python Modules Flashcards
What is a Python module?
A Python module is a Python file that contains code, such as functions, classes, or variables, which can be used in another Python file.
The file extension of a Python module is .py.
Examples of common modules: math, random, statistics.
How do you import a module in Python?
- import statement: Imports the entire module.
Example: import math
- from statement: Imports specific functions or attributes from a module.
Example: from math import sqrt
- import *: Imports all objects from a module.
Example: from math import *
Module Aliasing
Module aliasing allows you to create a nickname for a module using the as keyword.
import random as r
r.randint(1, 10) # Use ‘r’ as an alias for ‘random’
What does math.pi return?
math.pi returns the value of the mathematical constant π (pi).
import math
math.pi # Output: 3.141592653589793
What does math.e return?
import statistics as s
s.mode([1, 4, 5, 7, 4]) # Output: 4
import math
math.e # Output: 2.718281828459045
What does math.sqrt() do?
math.sqrt() returns the square root of a number.
Syntax: math.sqrt(number)
import math
math.sqrt(25) # Output: 5.0
What does math.ceil() do?
math.ceil() returns the smallest integer greater than or equal to a given number.
Syntax: math.ceil(x)
import math
math.ceil(4.5) # Output: 5
What does math.floor() do?
math.floor() returns the largest integer less than or equal to a given number.
Syntax: math.floor(x)
import math
math.floor(4.5) # Output: 4
What does math.pow() do?
math.pow() returns the value of x raised to the power of y.
Syntax: math.pow(x, y)
import math
math.pow(3, 2) # Output: 9.0
What does math.fabs() do?
math.fabs() returns the absolute value of a number (always positive).
Syntax: math.fabs(x)
import math
math.fabs(-10) # Output: 10.0
What does math.sin() do?
math.sin() returns the sine of an angle (in radians).
Syntax: math.sin(x)
import math
math.sin(0.524) # Output: 0.5003474302699141 (approx sine o
What does math.cos() do?
math.cos() returns the cosine of an angle (in radians).
Syntax: math.cos(x)
import math
math.cos(0.524) # Output: 0.8658247218821448 (approx cosine
What does math.tan() do?
math.tan() returns the tangent of an angle (in radians).
Syntax: math.tan(x)
import math
math.tan(0.524) # Output: 0.5778853590392409 (approx tangen
What does random.random() do?
random.random() generates a random float between 0.0 and 1.0 (inclusive of 0.0, exclusive of 1.0).
Syntax: random.random()
import random as r
r.random() # Output: 0.13939737870230484 (random flo
What does random.randint() do?
random.randint() generates a random integer between two specified numbers (inclusive).
Syntax: random.randint(a, b)
import random as r
r.randint(4, 9) # Output: 5 (random integer between
What does random.randrange() do?
random.randrange() generates a random integer between a start and stop value (start inclusive, stop exclusive).
Syntax: random.randrange(start, stop, step)
import random as r
r.randrange(4, 9) # Output: 5 (random integer betwee
What does statistics.mean() do?
statistics.mean() calculates the arithmetic mean (average) of a dataset.
Syntax: statistics.mean(data)
import statistics as s
s.mean([1, 4, 5, 7, 4]) # Output: 4.2
What does statistics.mode() do?
statistics.mode() calculates the mode (most frequent value) of a dataset.
Syntax: statistics.mode(data)
import statistics as s
s.mode([1, 4, 5, 7, 4]) # Output: 4
What does statistics.median() do?
statistics.median() calculates the median (middle value) of a dataset.
Syntax: statistics.median(data)
import statistics as s
s.median([1, 4, 5, 7, 4]) # Output: 4
