๐ Day 1: Line Chart in Python – Visualize Trends Like a Pro
When working with data, one of the most common questions we ask is:
“How does this value change over time?”
That’s exactly where a Line Chart comes in.
Welcome to Day 1 of the “50 Days of Python Data Visualization” series, where we explore one essential chart every day using Python.
๐ What is a Line Chart?
A line chart is a data visualization technique used to show trends and changes over time.
It connects individual data points with straight lines, making it easy to:
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Identify upward or downward trends
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Spot sudden spikes or drops
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Compare growth patterns
✅ When Should You Use a Line Chart?
Use a line chart when:
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Data is time-based (days, months, years)
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You want to track progress or trends
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Order of values matters
Real-world examples:
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Website traffic over months
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Stock prices over days
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Temperature changes during a week
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App downloads over time
❌ When NOT to Use a Line Chart
Avoid line charts when:
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Data is categorical → use a bar chart
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You want to show relationships → use a scatter plot
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Order of data does not matter
๐ Example Dataset
Let’s say we want to visualize website visitors over 6 months.
| Month | Visitors |
|---|---|
| Jan | 120 |
| Feb | 150 |
| Mar | 180 |
| Apr | 160 |
| May | 200 |
| Jun | 240 |
๐ง Python Code: Line Chart Using Matplotlib
๐งฉ Code Explanation (Simple Words)
plt.plot() → creates the line chart
marker='o' → shows dots on each data point
xlabel() and ylabel() → label the axes
title() → adds chart title
show() → displays the chart
๐ Key Takeaways
✔ Line charts show trends over time
✔ Order of x-axis values is very important
✔ Simple, powerful, and widely used in data science

