Random Chart Generation with Altair and Pandas

The function generates a random chart based on a provided DataFrame and chart type. The function first randomly selects fields from the DataFrame, then generates the corresponding Altair chart based on the chart type (bar, line, or scatter).

Technology Stack : Altair, Pandas

Code Type : Python Function

Code Difficulty : Intermediate

                
                    
import random
import altair as alt
import pandas as pd

def generate_random_chart(dataframe, chart_type):
    """
    Generates a random chart from a given dataframe and chart type.

    Parameters:
    - dataframe (pandas.DataFrame): The dataframe to use for generating the chart.
    - chart_type (str): The type of chart to generate (e.g., 'bar', 'line', 'scatter').

    Returns:
    - alt.Chart: The generated chart.
    """

    # Select random fields from the dataframe to use in the chart
    field1 = random.choice(dataframe.columns)
    field2 = random.choice(dataframe.columns)
    if field1 == field2:
        field2 = random.choice([col for col in dataframe.columns if col != field1])

    # Generate the chart based on the chart type
    if chart_type == 'bar':
        chart = alt.Chart(dataframe).mark_bar().encode(
            x=field1,
            y='count()'
        )
    elif chart_type == 'line':
        chart = alt.Chart(dataframe).mark_line().encode(
            x=field1,
            y=field2
        )
    elif chart_type == 'scatter':
        chart = alt.Chart(dataframe).mark_point().encode(
            x=field1,
            y=field2
        )
    else:
        raise ValueError("Unsupported chart type. Choose from 'bar', 'line', 'scatter'.")

    return chart

# Example usage
data = pd.DataFrame({
    'Category': ['A', 'B', 'C', 'D'],
    'Value': [10, 20, 30, 40]
})

chart = generate_random_chart(data, 'bar')
chart.display()