原来Python2 的round()是四舍五入,而 Python3 的round()为四舍六入五成双,即高位为单数则进1凑成双数,高位为双数则不进位。 这让我想起了大二时候的大物实验,第一节讲的计数方法,其中印象最深刻的就是“四舍六入五成双”,它的作用是让统计数据更公平,降低舍入的误差。 具体查阅: 浮点算术:争议和限制 ...
在Python语言中,我们通常会使用内置函数round来完成这个功能,保留指定位数的小数。 round的用法非常简单。例如: 那么,这个函数是否就是一个完美的解决方案呢?答案是否定的,round这个函数存在这样几个缺点。 1,round有时候无法正确地四舍五入。 实际上round这个函数的舍入的原则是:四舍六入五平分。 "五平分"就是出...
So, round() rounds 1.5 up to 2, and 2.5 down to 2!Before you go raising an issue on the Python bug tracker, rest assured you that round(2.5) is supposed to return 2. There’s a good reason why round() behaves the way it does....
Python does have two methods that let you round up and down. The floor() method rounds down to the nearest integer. ceil() rounds up to the nearest integer. We’ll focus on the round() method in this guide. You can read more about ceil() and floor() in ourPython guide to ceil()...
你好,我是zhen guo! 四舍五入4.5,应该返回结果5,但是使用Python或NumPy内置的round方法计算,结果都返回结果4 先来还原一下: In [1]: round(4.5) Out[1]: 4 In [2]: import numpy as np In [3]: np.round(4.5) Out[...
Python math module providesceil()andfloor()functions to rounded up and rounded down the any value. The floor and ceiling functions generally map a real number to the largest previous or smallest following integer which has zero decimal places. So to use them for 2 decimal places the number is...
Python program to round a numpy array# Import numpy import numpy as np # Import pandas import pandas as pd # Creating a numpy array arr = np.array([0.015, 0.235, 0.112]) # Display original array print("Original array:\n",arr,"\n") # Using round function res = np.round(arr, 2)...
You can also think of it as Round up going to the right of the number line while Round down moves towards the left. Now that we know what Round Down is, let's look at how to round down values in programming. How to Round Down a Number in Python? There are various methods to ...
What do you expect to happen now? You end up with -13. Python doesn’t round to an absolute value (you’d need ABS() for that), but preserves signage. round(0.12345) What happens if the rounding would be 0? Well, it does in fact return 0. Because it’s less than 0.5, it will...
Q4. In Python, the round() function rounds up or down? The round() function can round the values up and down both depending on the situation. For <0.5, it rounds down, and for >0.5, it rounds up. For =0.5, the round() function rounds the number off to the nearest even number....