https://www.mayuan.site/tags/python/ Recent content in Python on Prime's blog Hugo -- gohugo.io en Fri, 17 Jan 2020 14:59:41 +0800 https://www.mayuan.site/post/python/pandas/ Fri, 17 Jan 2020 14:59:41 +0800 https://www.mayuan.site/post/python/pandas/ pandas dataframe isnull vs isna These two DataFrame methods do exactly the same thing! In short: To detect NaN values numpy uses np.isnan(). To detect NaN values pandas uses either .isna() or .isnull(). The NaN values are inherited from the fact that pandas is built on top of numpy, while the two functions’ names originate from R’s DataFrames, whose structure and functionality pandas tried to mimic. QA 基本操 https://www.mayuan.site/post/python/fluent/ Wed, 27 Nov 2019 10:36:28 +0800 https://www.mayuan.site/post/python/fluent/ 流畅的python笔记 python数据模型 首先明确一点，特殊方法的存在是为了被 Python 解释器调用的，你自己并不需要调用它 们。也就是说没有 my_object.__len__() 这种写法