list of python examples

handling text files

handling text files is very easy.

check below code to open and read any text file.

# open, read lines and print
text_file = '_data/dummy_file.txt'

with open(text_file, 'r') as fh:
    text_file_content = fh.readlines()
    print(*text_file_content)

# open, read lines and print text_file = '_data/dummy_file.txt' with open(text_file, 'r') as fh: text_file_content = fh.readlines() print(*text_file_content)

handling csv files using pandas

# install pandas
%pip install pandas

# install pandas %pip install pandas

# import package
import pandas as pd

# read csv file
csv_file = '_data/random_data_from_web.csv'
csv_data = pd.read_csv(csv_file)

# fetch and print one of the column values
customer_ids = csv_data['Customer Id']
print(customer_ids)

# import package import pandas as pd # read csv file csv_file = '_data/random_data_from_web.csv' csv_data = pd.read_csv(csv_file) # fetch and print one of the column values customer_ids = csv_data['Customer Id'] print(customer_ids)

open site url in default web browser

# import package
import webbrowser

# open url using the default browser
site_url = 'https://github.com/chaitu-ycr/python_notes'
webbrowser.open(url=site_url)

# import package import webbrowser # open url using the default browser site_url = 'https://github.com/chaitu-ycr/python_notes' webbrowser.open(url=site_url)

create simple GUI using tkinter

# import package
import tkinter as tk

class GUI(tk.Tk):
    def __init__(self):
        super().__init__()
        self.title("Hello Button Example")
        
        # Set the window size (width x height)
        self.geometry("200x100")  # Adjust the dimensions as needed

        # Create a button
        clickButton = tk.Button(self, text='PressMe😋', command=self.say_hello)
        clickButton.pack()

        # Create a label
        self.textLabel = tk.Label(self, text="Press Button to say Hello...")
        self.textLabel.pack()

    def say_hello(self):
        # Update the label with text
        self.textLabel.configure(text='Helooo..😴')

# Create an instance of the GUI class
gui = GUI()
# Start the GUI event loop
gui.mainloop()

# import package import tkinter as tk class GUI(tk.Tk): def __init__(self): super().__init__() self.title("Hello Button Example") # Set the window size (width x height) self.geometry("200x100") # Adjust the dimensions as needed # Create a button clickButton = tk.Button(self, text='PressMe😋', command=self.say_hello) clickButton.pack() # Create a label self.textLabel = tk.Label(self, text="Press Button to say Hello...") self.textLabel.pack() def say_hello(self): # Update the label with text self.textLabel.configure(text='Helooo..😴') # Create an instance of the GUI class gui = GUI() # Start the GUI event loop gui.mainloop()

create simple browser based user interface page using dash

# import package
import dash
from dash import dcc
from dash import html
from dash.dependencies import Input, Output

# Create a Dash app
app = dash.Dash(__name__)

# Define the layout
app.layout = html.Div([
    html.Button("Say Hello", id="hello-button"),
    html.H3(id="output-label")
])

# Callback to update the label when the button is pressed
@app.callback(
    Output("output-label", "children"),
    [Input("hello-button", "n_clicks")]
)
def update_label(n_clicks):
    if n_clicks:
        return "Hello, World!"
    else:
        return ""

if __name__ == "__main__":
    app.run_server(debug=True)

# import package import dash from dash import dcc from dash import html from dash.dependencies import Input, Output # Create a Dash app app = dash.Dash(__name__) # Define the layout app.layout = html.Div([ html.Button("Say Hello", id="hello-button"), html.H3(id="output-label") ]) # Callback to update the label when the button is pressed @app.callback( Output("output-label", "children"), [Input("hello-button", "n_clicks")] ) def update_label(n_clicks): if n_clicks: return "Hello, World!" else: return "" if __name__ == "__main__": app.run_server(debug=True)

open images using opencv and pillow

# install packages
%pip install opencv-python

# install packages %pip install opencv-python

example 1: opening local image using opencv

# import package
import cv2

# Read an image from a file
image_path = "_data/dummy_image.jpg"  # Replace with the actual path to your image
img = cv2.imread(image_path, cv2.IMREAD_COLOR)

# Check if the image was loaded successfully
if img is not None:
    # Display the image in a window
    cv2.imshow("Image", img)
    cv2.waitKey(0)  # Wait for a key press (0 means indefinitely)
    cv2.destroyAllWindows()  # Close the window

else:
    print("Error loading the image. Please check the file path.")

# import package import cv2 # Read an image from a file image_path = "_data/dummy_image.jpg" # Replace with the actual path to your image img = cv2.imread(image_path, cv2.IMREAD_COLOR) # Check if the image was loaded successfully if img is not None: # Display the image in a window cv2.imshow("Image", img) cv2.waitKey(0) # Wait for a key press (0 means indefinitely) cv2.destroyAllWindows() # Close the window else: print("Error loading the image. Please check the file path.")

example 2: opening online image using pillow

# import package
from PIL import Image
import requests
from io import BytesIO

# Replace the URL with the actual image URL
url = "https://picsum.photos/200"

# Fetch the image data from the URL
response = requests.get(url)
image_data = BytesIO(response.content)

# Open the image using PIL
image = Image.open(image_data)

# Display the image
image.show()

# import package from PIL import Image import requests from io import BytesIO # Replace the URL with the actual image URL url = "https://picsum.photos/200" # Fetch the image data from the URL response = requests.get(url) image_data = BytesIO(response.content) # Open the image using PIL image = Image.open(image_data) # Display the image image.show()

creating python packages using poetry

create python tests using pytest

create HTML test reports using pytest-html

multithreading

regular expressions

create executables using pyinstaller