Customizing Plots

Why Customize?

Default plots work, but custom plots:

Look more professional
Match your brand
Are easier to read

Change Font Sizes

code.py

import matplotlib.pyplot as plt

fig, ax = plt.subplots()
ax.plot([1, 2, 3], [1, 4, 9])

ax.set_title('My Chart', fontsize=16)
ax.set_xlabel('X Axis', fontsize=12)
ax.set_ylabel('Y Axis', fontsize=12)

plt.show()

Change Tick Label Size

code.py

ax.tick_params(axis='both', labelsize=10)

Use Different Colors

code.py

# Named colors
ax.plot(x, y, color='red')
ax.plot(x, y, color='steelblue')

# Hex colors
ax.plot(x, y, color='#3498db')

# RGB (0-1 scale)
ax.plot(x, y, color=(0.2, 0.6, 0.8))

Use Color Palettes

code.py

# Built-in colors
colors = plt.cm.tab10.colors  # 10 distinct colors

for i, color in enumerate(colors[:5]):
    ax.plot([1, 2, 3], [i, i+1, i+2], color=color)

Add Grid

code.py

ax.grid(True)

# Customize grid
ax.grid(True, linestyle='--', alpha=0.5, color='gray')

Change Line Width

code.py

ax.plot(x, y, linewidth=2)  # or lw=2

Add Legend

code.py

ax.plot(x, y1, label='Series 1')
ax.plot(x, y2, label='Series 2')
ax.legend(loc='upper right')

Locations: 'upper right', 'upper left', 'lower right', 'lower left', 'center'

Set Background Color

code.py

ax.set_facecolor('#f0f0f0')  # Light gray background

Remove Borders (Spines)

code.py

ax.spines['top'].set_visible(False)
ax.spines['right'].set_visible(False)

Use Built-in Styles

code.py

# See available styles
print(plt.style.available)

# Use a style
plt.style.use('seaborn-v0_8')
# or
plt.style.use('ggplot')

Popular styles: 'ggplot', 'seaborn-v0_8', 'fivethirtyeight', 'dark_background'

Complete Example

code.py

import matplotlib.pyplot as plt

# Use a nice style
plt.style.use('seaborn-v0_8-whitegrid')

# Data
months = ['Jan', 'Feb', 'Mar', 'Apr', 'May']
sales = [100, 120, 115, 140, 160]

# Create figure
fig, ax = plt.subplots(figsize=(10, 6))

# Plot with custom styling
ax.plot(months, sales, marker='o', color='#2ecc71',
        linewidth=2, markersize=8)

# Titles and labels
ax.set_title('Monthly Sales', fontsize=16, fontweight='bold')
ax.set_xlabel('Month', fontsize=12)
ax.set_ylabel('Sales ($K)', fontsize=12)

# Remove top and right borders
ax.spines['top'].set_visible(False)
ax.spines['right'].set_visible(False)

# Customize ticks
ax.tick_params(axis='both', labelsize=11)

plt.tight_layout()
plt.show()

Key Customization Options

What	How
Title size	fontsize=16
Line width	linewidth=2
Marker size	markersize=8
Transparency	alpha=0.5
Grid	grid(True)
Legend	legend()
Style	plt.style.use()

Key Points

fontsize changes text size
linewidth changes line thickness
alpha adds transparency
plt.style.use() for quick themes
Remove spines for cleaner look
Always use tight_layout() to prevent overlap

What's Next?

Learn to create multiple charts in one figure with subplots.