Code Editor for app.py

import streamlit as st
import pandas as pd
import altair as alt
import seaborn as sns

@st.cache_data
def load_data(url):
    # NOTE: Using corsproxy.io because we're in a WASM environment. If running locally,
    # you can remove the corsproxy.io prefix.
    if not url.startswith('https://corsproxy.io/?'):
        url = f'https://corsproxy.io/?{url}'
    return pd.read_csv(url)

# URL input
url = st.text_input(
    'Enter CSV URL',
    value='https://raw.githubusercontent.com/mwaskom/seaborn-data/master/penguins.csv'
)

try:
    # Load data
    df = load_data(url)
    
    # Controls
    col1, col2 = st.columns(2)
    
    with col1:
        n_rows = st.number_input('Number of rows to display', 
                                min_value=1, 
                                max_value=len(df),
                                value=min(10, len(df)))
    
    with col2:
        shuffle = st.checkbox('Randomly shuffle data')
    
    if shuffle:
        df = df.sample(frac=1).reset_index(drop=True)
    
    # Display dataframe
    st.dataframe(df.head(n_rows))
    
    # Variable selection
    st.subheader('Visualization')
    columns = df.select_dtypes(include=['float64', 'int64']).columns.tolist()
    
    col1, col2 = st.columns(2)
    with col1:
        var1 = st.selectbox('Select first variable', columns)
    with col2:
        var2 = st.selectbox('Select second variable', 
                           [None] + [col for col in columns if col != var1])
    
    # Visualization logic
    if var2:
        # If two variables selected, create a scatter plot
        chart = alt.Chart(df).mark_circle().encode(
            x=var1,
            y=var2,
            tooltip=[var1, var2]
        ).properties(
            width=600,
            height=400,
            title=f'{var1} vs {var2}'
        )
        st.altair_chart(chart, use_container_width=True)
    else:
        # If one variable selected, create a histogram
        chart = alt.Chart(df).mark_bar().encode(
            x=alt.X(var1, bin=True),
            y='count()',
            tooltip=['count()']
        ).properties(
            width=600,
            height=400,
            title=f'Distribution of {var1}'
        )
        st.altair_chart(chart, use_container_width=True)

except Exception as e:
    st.error(f'Error loading data: {str(e)}')