Data Visualization with Matplotlib

In this module we will learn how to visualize data using Matplotlib, a powerful plotting library in Python. We will cover various types of plots including line charts, bar charts, histograms, scatter plots, pie charts, and box plots.

import pandas as pd
import numpy as np

df = pd.read_csv('diabetes.csv')

import matplotlib.pyplot as plt

Line Chart

#Parameter: x, y Coordinates for data points
age = [3, 6, 9, 12, 15, 18, 21, 24]
Mike = [95, 120, 141, 159, 174, 185, 187, 187]
George = [99, 126, 145, 163, 179, 191, 191, 191]

plt.plot(age, Mike, color='blue', linewidth=3, marker='o', markersize=8, linestyle='--')

plt.plot(age, George, color='red', linewidth=3, marker='o', markersize=8, linestyle='--')

plt.title("Line Chart")
plt.ylabel('Height (cm)')
plt.xlabel('Age (years)')
plt.legend(labels=('Mike', 'George'))
plt.show()

Bar Chart

# This code creates a simple bar chart to show total bills for different days.
# X-axis represents the days and Y-axis shows total bill amount.
x = ['Thur', 'Fri', 'Sat', 'Sun']
y = [170, 120, 250, 190]

plt.bar(x, y, color='green', edgecolor='black', linewidth=2)
plt.title("Bar Chart")
plt.xlabel("Day")
plt.ylabel("Total Bill")
plt.show()

Histogram

pregnancies = df['Pregnancies']

plt.hist(pregnancies, bins=10, color='steelblue', edgecolor='black',linestyle='--')
plt.title("Histogram")
plt.xlabel("Number of Pregnancy")
plt.ylabel("Frequency")
plt.show()

Scatter Plot

BMI = df['BMI']
BloodPressure = df['BloodPressure']

plt.scatter(BMI, BloodPressure, s = 15)
plt.title("Scatter Plot")
plt.xlabel("BMI")
plt.ylabel("Blood Pressure")

b, a = np.polyfit(BMI, BloodPressure, 1)

plt.plot(BMI, b*BMI + a, color='red', linewidth=2)
plt.show()

Pie Chart

# This code creates a simple pie chart to visualize distribution of different car brands.
# Each slice of pie represents the proportion of cars for each brand in the dataset.
cars = ['AUDI', 'BMW', 'FORD','TESLA', 'JAGUAR',]
data = [23, 10, 35, 15, 12]
explode = [0.1, 0.5, 0, 0, 0]
colors = ( "orange", "cyan", "yellow","grey", "green")

plt.pie(data, labels=cars, explode=explode, colors=colors, autopct='%d%%', shadow = True)
#plt.title("Pie Chart")
plt.show()

Box Plot

Pregnancies = df['Pregnancies']
Glucose = df['Glucose']
BloodPressure = df['BloodPressure']
SkinThickness = df['SkinThickness']
Age = df['Age']

data = Pregnancies

plt.boxplot(data)
plt.xlabel("Groups")
plt.ylabel("Values")
plt.title("Box Plot")
plt.show()