How to understand what Python elements (?) are doing

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How to understand what Python elements (?) are doing

posted Oct 23, 2018

Getting Started numpy/pandas

Hi,
I'm a newbie to Python. I have programmed in R and am struggling a little when trying to follow along with some of the code written and shared on these forums.

I am working through the (Machine Learning on Quantopian code and am stuck because I cannot understand what these functions are doing...

results_wo_returns = results.copy()  
returns = results_wo_returns.pop('Returns')  
Y = returns.unstack().values  
X = results_wo_returns.to_panel()  
X = X.swapaxes(2, 0).swapaxes(0, 1).values # (factors, time, stocks) -> (time, stocks, factors)

For copy, I was able to lookup via np.copy? though I am not sure if this is correct given its being run on results which is a pandas dataframe. For the other elements, I cannot find these definitions.

Another thing I don't understand is where Returns is suddenly dropped in results_wo_returns

I appreciate this is a pretty basic question, but I'm struggling to progress without understanding this, and am not even sure what to google.

Much appreciated,
J

1 response

I figured this out by googling python and the function. I thought this would be in the documentation using the ? as advised. I don't appear to be able to delete my own question so leaving it here in case some one else has the same question some time later.

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The material on this website is provided for informational purposes only and does not constitute an offer to sell, a solicitation to buy, or a recommendation or endorsement for any security or strategy, nor does it constitute an offer to provide investment advisory services by Quantopian.

In addition, the material offers no opinion with respect to the suitability of any security or specific investment. No information contained herein should be regarded as a suggestion to engage in or refrain from any investment-related course of action as none of Quantopian nor any of its affiliates is undertaking to provide investment advice, act as an adviser to any plan or entity subject to the Employee Retirement Income Security Act of 1974, as amended, individual retirement account or individual retirement annuity, or give advice in a fiduciary capacity with respect to the materials presented herein. If you are an individual retirement or other investor, contact your financial advisor or other fiduciary unrelated to Quantopian about whether any given investment idea, strategy, product or service described herein may be appropriate for your circumstances. All investments involve risk, including loss of principal. Quantopian makes no guarantees as to the accuracy or completeness of the views expressed in the website. The views are subject to change, and may have become unreliable for various reasons, including changes in market conditions or economic circumstances.