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How do I retrieve the number of columns in a Pandas data frame?
...rocessing speed sometimes, but I value my coding time and code readability more than a few seconds of processing time. In this particular case: if you learn that the number of rows can be calculated with len(df.index), next time you need the number of columns it comes natural to do len(df.columns).
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How do I design a class in Python?
...r namedtuples, and you don't need to do very much work. Other classes are more complex, either because of complex derived data or because of some update/mutation which is performed.
Don't forget to test each class in isolation using unittest.
Also, there's no law that says classes must be mutabl...
“implements Runnable” vs “extends Thread” in Java
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How do I download a tarball from GitHub using cURL?
...curl: (60) SSL certificate problem: unable to get local issuer certificate More details here: curl.haxx.se/docs/sslcerts.html curl performs SSL certificate verification by default, using a "bundle".. If you'd like to turn off curl's verification of the certificate, use the -k (or --insecure) opti...
How to install trusted CA certificate on Android device?
...asy. Installing new certificates as 'system trusted'-certificates requires more work (and requires root access), but it has the advantage of avoiding the Android lockscreen requirement.
From Android N onwards it gets a littler harder, see this extract from the Charles proxy website:
As of Andr...
Web-scraping JavaScript page with Python
...date it. The old answer is still at the end.
dryscape isn't maintained anymore and the library dryscape developers recommend is Python 2 only. I have found using Selenium's python library with Phantom JS as a web driver fast enough and easy to get the work done.
Once you have installed Phantom JS,...
Fastest way to convert Image to Byte array
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@FirstStep Not quite. More accurately: If you use an object that has implemented IDisposable, then you should be sure to call Dispose() when you're done with it so that it'll clean up any resources that it has tied up. The using(){} statement just...
std::shared_ptr of this
...e point of call. This means that you cannot create such object on stack anymore, and generally cannot call .shared_from_this() from within a constructor or destructor.
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Good ways to manage a changelog using git?
...le now, and I recently started using it to tag my releases so that I could more easily keep track of changes and be able to see which version each of our clients are running (unfortunately the code currently mandates that each client have their own copy of the PHP site; I'm changing this, but it's s...