Rounding Decimals
🔢 Rounding Decimals in Python
Python provides several ways to round numbers to a specific number of decimal places. You can use built-in functions, string formatting, or NumPy for arrays.
1. Using round() Function
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Syntax:
round(number, digits) -
digitsis optional; default is 0
2. Using String Formatting
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.2f→ 2 decimal places -
.3f→ 3 decimal places
3. Using math.floor() and math.ceil()
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floor()→ largest integer ≤ number -
ceil()→ smallest integer ≥ number
4. Using NumPy for Arrays
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np.round()→ rounds to specified decimals -
np.floor()→ element-wise floor -
np.ceil()→ element-wise ceiling
✅ 5. Using decimal Module for Precision Control
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Provides precise decimal rounding
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Useful in financial calculations
🎯 Practice Exercises
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Round
5.6789to 0, 1, 2, 3 decimal places. -
Create a NumPy array
[2.345, 6.789, 1.234]and round it to 2 decimals. -
Use the
decimalmodule to round7.555to 2 decimal places usingROUND_HALF_UP.
