Dates on x-axis in Matplotlib - Mini Project: Build & Apply

Dates on x-axis

📖 Scenario: You work in a small bakery. You want to see how many cakes you sold each day last week. You have the dates and the number of cakes sold. You want to make a simple line chart with dates on the x-axis and cakes sold on the y-axis.

🎯 Goal: Create a line chart using matplotlib that shows the number of cakes sold each day last week. The x-axis should show the dates properly formatted.

📋 What You'll Learn

Create a list of dates for 7 days from 2024-04-01 to 2024-04-07

Create a list of integers for cakes sold each day

Use matplotlib to plot the dates on the x-axis and cakes sold on the y-axis

Format the x-axis to show dates clearly

💡 Why This Matters

🌍 Real World

Plotting dates on the x-axis is common in sales, weather, finance, and many other fields where data changes over time.

💼 Career

Data scientists and analysts often need to visualize time series data clearly to find trends and patterns.

1

Create the dates and sales data

Create a list called dates with these exact date strings: '2024-04-01', '2024-04-02', '2024-04-03', '2024-04-04', '2024-04-05', '2024-04-06', '2024-04-07'. Also create a list called cakes_sold with these exact numbers: 10, 15, 7, 12, 9, 14, 11.

Matplotlib

# Create the dates list and cakes_sold list
# Your code here

Need a hint?

Use a list for dates with the exact date strings. Use a list for cakes_sold with the exact numbers.

2

Convert date strings to datetime objects

Import datetime from datetime module. Create a new list called date_objects by converting each string in dates to a datetime object using datetime.strptime with format '%Y-%m-%d'.

Matplotlib

dates = ['2024-04-01', '2024-04-02', '2024-04-03', '2024-04-04', '2024-04-05', '2024-04-06', '2024-04-07']
cakes_sold = [10, 15, 7, 12, 9, 14, 11]
# Convert dates strings to datetime objects
# Your code here

Need a hint?

Use a list comprehension to convert each date string to a datetime object.

3

Plot the data with dates on x-axis

Import matplotlib.pyplot as plt. Use plt.plot to plot date_objects on the x-axis and cakes_sold on the y-axis. Use plt.gcf().autofmt_xdate() to format the dates on the x-axis nicely.

Matplotlib

from datetime import datetime

dates = ['2024-04-01', '2024-04-02', '2024-04-03', '2024-04-04', '2024-04-05', '2024-04-06', '2024-04-07']
cakes_sold = [10, 15, 7, 12, 9, 14, 11]

date_objects = [datetime.strptime(date, '%Y-%m-%d') for date in dates]
# Import matplotlib and plot the data
# Your code here

Need a hint?

Use plt.plot to draw the line. Use plt.gcf().autofmt_xdate() to rotate date labels.

4

Show the plot

Add a line to display the plot using plt.show().

Matplotlib

from datetime import datetime
import matplotlib.pyplot as plt

dates = ['2024-04-01', '2024-04-02', '2024-04-03', '2024-04-04', '2024-04-05', '2024-04-06', '2024-04-07']
cakes_sold = [10, 15, 7, 12, 9, 14, 11]

date_objects = [datetime.strptime(date, '%Y-%m-%d') for date in dates]

plt.plot(date_objects, cakes_sold)
plt.gcf().autofmt_xdate()
# Show the plot
# Your code here

Need a hint?

Use plt.show() to display the plot window.