大 pandas 获得两列的最小值作为方程式的一部分 [英] pandas get minimum value of two columns as part of an equation

问题描述

如何作为熊猫数据框方程的一部分引用两个数据框的最小值?我尝试使用无法正常工作的python min()函数.很抱歉，如果在某处对此进行了详细记录，但我无法找到解决此问题的可行解决方案.我正在寻找与此类似的东西:

How can I reference the minimum value of two dataframes as part of a pandas dataframe equation? I tried using the python min() function which did not work. I'm sorry if this is well-documented somewhere but I have not been able to find a working solution for this problem. I am looking for something along the lines of this:

data['eff'] = pd.DataFrame([data['flow_h'], data['flow_c']]).min() *Cp* (data[' Thi'] - data[' Tci'])

我还尝试了使用熊猫min()函数，该函数也不起作用.

I also tried to use pandas min() function, which is also not working.

min_flow = pd.DataFrame([data['flow_h'], data['flow_c']]).min()

InvalidIndexError: Reindexing only valid with uniquely valued Index objects

这个错误让我感到困惑.数据列只是数字和名称，我不确定索引在哪里起作用.

I was confused by this error. The data columns are just numbers and a name, I wasn't sure where the index comes into play.

In [108]: data['flow_c']
Out[108]: 
0       74.014640
1       74.150579
2       74.014640
3       73.960195
4       74.069046
5       73.960195
6       73.987423
7       73.905710

推荐答案

您的问题对我来说不是很清楚，但是我的猜测是，您正在尝试获取两个Series中的元素级mininum(不是DataFrame s).如果那是您想要的，请尝试:data[['flow_h','flow_c']].min(axis=1).

Your question is not very clear to me, but my guess is that you are trying to get element-wise mininum of two Series (not DataFrames). If that's what you want, try: data[['flow_h','flow_c']].min(axis=1).

这篇关于大 pandas 获得两列的最小值作为方程式的一部分的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！