1. 使用`round()`函数:
```python
number = 3.14159
rounded_number = round(number, 2)
print(rounded_number) 输出:3.14
2. 使用字符串格式化(`%`操作符):
```python
number = 3.14159
formatted_number = "%.2f" % number
print(formatted_number) 输出:3.14
3. 使用`format()`函数:
```python
number = 3.14159
formatted_number = format(number, ".2f")
print(formatted_number) 输出:3.14
4. 使用`decimal`模块:
```python
from decimal import Decimal
number = Decimal('3.14159')
formatted_number = number.quantize(Decimal('0.00'))
print(formatted_number) 输出:3.14
5. 使用`f-string`(Python 3.6及以上版本):
```python
number = 3.14159
formatted_number = f"{number:.2f}"
print(formatted_number) 输出:3.14
6. 使用`numpy`库(如果需要处理大量数据):
```python
import numpy as np
number = np.array([3.14159])
formatted_number = np.around(number, 2)
print(formatted_number) 输出:[3.14]
以上方法都可以用来保留浮点数的小数点后两位。选择哪种方法取决于你的具体需求,例如是否需要高精度计算、是否处理大量数据等