How to change the space between bars when drawing multiple barplots in Pandas? (Matplotlib)

To change the space between bars when drawing multiple barplots in Pandas, you can use the width parameter in the plot() method to control bar width, or edgecolor and linewidth to create visual separation between bars.

Method 1: Using Width Parameter

The width parameter controls the width of each bar, which indirectly affects the spacing ?

import pandas as pd
import matplotlib.pyplot as plt

# Sample data
data = {
    'Column 1': [i for i in range(5)],
    'Column 2': [i * i for i in range(5)]
}

df = pd.DataFrame(data)

# Plot with different bar widths
fig, axes = plt.subplots(1, 2, figsize=(12, 4))

# Default width
df.plot(kind='bar', ax=axes[0], title='Default Width')

# Reduced width (more space between bars)
df.plot(kind='bar', ax=axes[1], width=0.6, title='Width=0.6')

plt.tight_layout()
plt.show()

Method 2: Using EdgeColor and LineWidth

Adding white edges with linewidth creates visual separation between grouped bars ?

import pandas as pd
import matplotlib.pyplot as plt

data = {
    'Sales Q1': [100, 150, 200, 120, 180],
    'Sales Q2': [120, 160, 190, 140, 200],
    'Sales Q3': [110, 140, 210, 130, 170]
}

df = pd.DataFrame(data, index=['Jan', 'Feb', 'Mar', 'Apr', 'May'])

# Plot with edge styling for separation
df.plot(kind='bar', 
        edgecolor='white', 
        linewidth=2,
        figsize=(10, 6),
        width=0.8)

plt.title('Quarterly Sales Data')
plt.ylabel('Sales Amount')
plt.legend(loc='upper left')
plt.xticks(rotation=45)
plt.show()

Method 3: Direct Matplotlib for Custom Spacing

For more control over spacing, use matplotlib directly with custom positioning ?

import pandas as pd
import matplotlib.pyplot as plt
import numpy as np

data = {
    'Product A': [25, 30, 35, 20],
    'Product B': [20, 25, 30, 25],
    'Product C': [15, 20, 25, 30]
}

df = pd.DataFrame(data, index=['Q1', 'Q2', 'Q3', 'Q4'])

# Custom bar positioning
x = np.arange(len(df.index))
width = 0.25  # Width of bars
spacing = 0.05  # Additional spacing

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

# Plot each column with custom positioning
for i, column in enumerate(df.columns):
    offset = (i - 1) * (width + spacing)
    ax.bar(x + offset, df[column], width, label=column)

ax.set_xlabel('Quarter')
ax.set_ylabel('Sales')
ax.set_title('Product Sales by Quarter')
ax.set_xticks(x)
ax.set_xticklabels(df.index)
ax.legend()

plt.show()

Comparison

Conclusion

Use the width parameter for quick bar width adjustments, edgecolor with linewidth for visual separation, or direct matplotlib for complete control over bar spacing and positioning.