Streamlit
1 Introduction to Streamlit
1.1 What is Streamlit?
1.2 Why use Streamlit?
1.3 Setting up the environment
1.4 Creating your first Streamlit app
2 Basic Components
2.1 Text elements
2.1 1 Displaying text
2.1 2 Formatting text
2.2 Data display elements
2.2 1 Displaying data frames
2.2 2 Displaying tables
2.3 Input widgets
2.3 1 Text input
2.3 2 Number input
2.3 3 Date input
2.3 4 Dropdown selection
2.3 5 Slider
2.3 6 Checkbox
2.3 7 Radio buttons
2.3 8 Buttons
3 Advanced Components
3.1 Interactive widgets
3.1 1 Multiselect
3.1 2 File uploader
3.1 3 Color picker
3.2 Media elements
3.2 1 Displaying images
3.2 2 Displaying videos
3.2 3 Displaying audio
3.3 Chart elements
3.3 1 Line chart
3.3 2 Bar chart
3.3 3 Area chart
3.3 4 Scatter chart
3.3 5 Map chart
4 Layout and Styling
4.1 Layout components
4.1 1 Columns
4.1 2 Tabs
4.1 3 Expander
4.2 Styling elements
4.2 1 Custom CSS
4.2 2 Theming
4.2 3 Adding custom fonts
5 State Management
5.1 Session state
5.1 1 Managing state across reruns
5.1 2 Persisting state
5.2 Caching
5.2 1 Caching functions
5.2 2 Caching data
6 Deployment
6.1 Deploying to Streamlit Sharing
6.1 1 Setting up Streamlit Sharing
6.1 2 Deploying your app
6.2 Deploying to other platforms
6.2 1 Deploying to Heroku
6.2 2 Deploying to AWS
6.2 3 Deploying to Google Cloud
7 Best Practices
7.1 Writing clean and maintainable code
7.2 Optimizing performance
7.3 Handling errors and exceptions
7.4 Version control with Git
8 Advanced Topics
8.1 Integrating with other libraries
8.1 1 Integrating with Pandas
8.1 2 Integrating with Plotly
8.1 3 Integrating with TensorFlow
8.2 Building complex apps
8.2 1 Creating multi-page apps
8.2 2 Handling authentication
8.2 3 Building interactive dashboards
8.3 Custom components
8.3 1 Creating custom widgets
8.3 2 Extending Streamlit with custom components
9 Case Studies
9.1 Building a data exploration app
9.2 Building a machine learning model deployment app
9.3 Building a real-time data visualization app
7 2 Optimizing Performance Explained

2 Optimizing Performance Explained

Key Concepts

Caching

Caching involves storing the results of expensive operations so that they can be reused without recomputing them. This is particularly useful in Streamlit apps where certain operations, such as data loading or complex calculations, can be time-consuming.

import streamlit as st

@st.cache
def expensive_computation(a, b):
    return a * b

result = expensive_computation(2, 21)
st.write(result)
    

Lazy Loading

Lazy loading is a technique where resources are loaded only when they are needed. This can significantly improve the performance of your Streamlit app by reducing the initial load time.

import streamlit as st

if st.button("Load Data"):
    data = load_data()
    st.write(data)
    

Efficient Data Handling

Efficient data handling involves techniques to manage and process data in a way that minimizes resource usage. This includes using data structures that are optimized for the task at hand and avoiding unnecessary data transformations.

import pandas as pd

data = pd.read_csv("large_dataset.csv")
data = data.sample(frac=0.1)  # Reduce dataset size for faster processing
st.write(data.head())
    

Minimizing Re-renders

Minimizing re-renders involves reducing the number of times the UI is updated. This can be achieved by grouping related updates together and using Streamlit's caching mechanisms to avoid unnecessary re-computations.

import streamlit as st

if "counter" not in st.session_state:
    st.session_state.counter = 0

if st.button("Increment"):
    st.session_state.counter += 1

st.write(f"Counter: {st.session_state.counter}")
    

Asynchronous Operations

Asynchronous operations involve performing tasks concurrently to improve responsiveness. This can be particularly useful for I/O-bound operations like fetching data from APIs or reading large files.

import streamlit as st
import asyncio

async def fetch_data():
    await asyncio.sleep(2)  # Simulate an async operation
    return "Data fetched"

if st.button("Fetch Data"):
    data = asyncio.run(fetch_data())
    st.write(data)
    

Analogies

Think of caching as a refrigerator where you store prepared meals. Instead of cooking a meal from scratch every time you're hungry, you can quickly grab a pre-cooked meal from the fridge. Lazy loading is like ordering food only when you're hungry, rather than stocking up on groceries before you need them. Efficient data handling is like organizing your kitchen to make cooking faster and easier. Minimizing re-renders is like planning your meals to avoid unnecessary trips to the grocery store. Asynchronous operations are like cooking multiple dishes at once, rather than waiting for one to finish before starting the next.

By mastering these optimization techniques, you can create high-performance Streamlit applications that efficiently handle complex computations and data processing tasks.