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How to check whether a pandas DataFrame is empty?
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To see if a dataframe is empty, I argue that one should test for the length of a dataframe's columns index:
if len(df.columns) == 0: 1
Reason:
According to the Pandas Reference API, there is a distinction between:
an empty dataframe with 0 rows and 0 columns
an empty dataframe w...
How to tell whether a point is to the right or left side of a line
... Should you find yourself in a situation where rounding error on this test is causing you problems, you will want to look up Jon Shewchuk's "Fast Robust Predicates for Computational Geometry".
– Stephen Canon
Oct 13 '09 at 15:13
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Can I multiply strings in Java to repeat sequences? [duplicate]
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StringUtils has been performance tuned and tested. The time to produce a production quality String utility library is time you don't have unless your current project is to write a production quality String utility library. Don't write code you don't have to. Plus, the...
Why doesn't this code simply print letters A to Z?
... the variable as a character. The for-loop would be more efficient if the test for the maximum value is determined only once as follows: "for ($i = ord('a'),$max = ord('z'); $i <= $max; $i++){"
– slevy1
Dec 1 '14 at 0:15
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Getting a better understanding of callback functions in JavaScript
...if the converted boolean returns true and then checking its type again and testing it against the string... Could you explain why?
– headacheCoder
Oct 21 '13 at 12:41
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Git push rejected after feature branch rebase
...rebase master
git merge -s ours old-feature
git push origin feature
(Not tested, but I think that's right...)
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How to check if a file exists in Go?
... See err for details.
// Therefore, do *NOT* use !os.IsNotExist(err) to test for file existence
}
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How can I remove duplicate rows?
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@Martin, @Georg: So, I've made a small test. A big table was created and populated as described here: sqlinthewild.co.za/index.php/2010/03/23/… Two SELECTs then were produced, one using the LEFT JOIN + WHERE IS NULL technique, the other using the NOT IN one. The...
HTTP headers in Websockets client API
...d" base64 encoded:
Authorization: Basic dXNlcm5hbWU6cGFzc3dvcmQ=
I have tested basic auth in Chrome 55 and Firefox 50 and verified that the basic auth info is indeed negotiated with the server (this may not work in Safari).
Thanks to Dmitry Frank's for the basic auth answer
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How to keep a Python script output window open?
...and have to remember removing it when you're done. Specially annoying when testing other people's scripts. For Python3, use input().
Use an editor that pauses for you. Some editors prepared for python will automatically pause for you after execution. Other editors allow you to configure the command...