Python Basics Cheat Sheet

Basics

# Print Statement
print("Hello, World!") # Variables
x = 5
y = "Hello" # Data Types
int_var = 10 # Integer
float_var = 10.5 # Float
str_var = "Hello" # String
bool_var = True # Boolean
list_var = [1, 2, 3] # List
tuple_var = (1, 2, 3) # Tuple
set_var = {1, 2, 3} # Set
dict_var = {"key": "value"} # Dictionary
Enter fullscreen mode
Exit fullscreen mode

Control Structures

# If-Else
if x > 0: print("Positive")
elif x == 0: print("Zero")
else: print("Negative") # For Loop
for i in range(5): print(i) # While Loop
count = 0
while count < 5: print(count) count += 1
Enter fullscreen mode
Exit fullscreen mode

Functions

def my_function(param1, param2): return param1 + param2 result = my_function(5, 3)
print(result)
Enter fullscreen mode
Exit fullscreen mode

Classes

class MyClass: def __init__(self, name): self.name = name def greet(self): return f"Hello, {self.name}!" obj = MyClass("Harlin")
print(obj.greet())
Enter fullscreen mode
Exit fullscreen mode

Exception Handling

try: result = 10 / 0
except ZeroDivisionError: print("Cannot divide by zero!")
finally: print("Execution complete.")
Enter fullscreen mode
Exit fullscreen mode

File Operations

# Read from a file
with open('file.txt', 'r') as file: content = file.read() print(content) # Write to a file
with open('file.txt', 'w') as file: file.write("Hello, World!")
Enter fullscreen mode
Exit fullscreen mode

List Comprehensions

# Basic List Comprehension
squares = [x**2 for x in range(10)]
print(squares) # Conditional List Comprehension
evens = [x for x in range(10) if x % 2 == 0]
print(evens)
Enter fullscreen mode
Exit fullscreen mode

Lambda Functions

# Lambda Function
add = lambda a, b: a + b
print(add(5, 3))
Enter fullscreen mode
Exit fullscreen mode

Map, Filter, Reduce

from functools import reduce # Map
numbers = [1, 2, 3, 4, 5]
squared = list(map(lambda x: x**2, numbers))
print(squared) # Filter
evens = list(filter(lambda x: x % 2 == 0, numbers))
print(evens) # Reduce
sum_numbers = reduce(lambda a, b: a + b, numbers)
print(sum_numbers)
Enter fullscreen mode
Exit fullscreen mode

Modules

# Importing a Module
import math
print(math.sqrt(16)) # Importing Specific Functions
from math import pi, sin
print(pi)
print(sin(0))
Enter fullscreen mode
Exit fullscreen mode

Numpy Basics

import numpy as np # Creating Arrays
arr = np.array([1, 2, 3, 4, 5])
print(arr) # Array Operations
print(arr + 5)
print(arr * 2)
print(np.sqrt(arr))
Enter fullscreen mode
Exit fullscreen mode

Pandas Basics

import pandas as pd # Creating DataFrame
data = { 'Name': ['Alice', 'Bob', 'Charlie'], 'Age': [24, 27, 22]
}
df = pd.DataFrame(data)
print(df) # Basic Operations
print(df['Name'])
print(df.describe())
print(df[df['Age'] > 23])
Enter fullscreen mode
Exit fullscreen mode

Matplotlib Basics

import matplotlib.pyplot as plt # Basic Plot
x = [1, 2, 3, 4, 5]
y = [2, 3, 5, 7, 11]
plt.plot(x, y)
plt.xlabel('x-axis')
plt.ylabel('y-axis')
plt.title('Sample Plot')
plt.show()
Enter fullscreen mode
Exit fullscreen mode

Discover more from Coursity

Subscribe to get the latest posts sent to your email.

Leave a Comment

Your email address will not be published. Required fields are marked *

Discover more from Coursity

Subscribe now to keep reading and get access to the full archive.

Continue reading

Scroll to Top
Simon says web design. Companies providing web hosting services are sometimes called web. Unlock your potential : start your journey to becoming a web developer today.