Add DataFrame.conj/conjugate

[changhiskhan]

From mailing list

I noticed that Series has methods .conj() and .conjugate() but dataframe does not. Doing a search on complex numbers in pandas, I found this issue.

#1083

Is there any hope of getting .conj() onto the dataframe? Or should I convert to an np-array, then convert back to a df?

[hughesadam87]

This may not be the robust solution that would be ideal, but isn't it easy enough to convert to an np array, conjugate, and then recast into a DataFrame?

df=DataFrame()
df_conj = DataFrame(np.asarray(df).conj(), index=df.index, columns=df.columns)

[wesm]

np.conj(df) should work too, no?

[hughesadam87]

Ah, you're right. I didn't realize np.conj() was a function, thought that .conj() only existed as an instance method of a numpy array. I guess this problem is solved, thanks.

[paulproteus]

@wesm or @changhiskhan -- which of the following is the best answer here:

• Close the ticket and mark it as resolved, or
• Have a new contributor write a simple .conj() or .conjugate() method for DataFrame

?

If the latter, that'd be great; the code would be super easy. If the former, then one of the maintainers should close it.

Thanks!

[wesm]

Closing-- I think ``np.conj(df)` is the preferred API for now