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Comparing two dataframes and getting the differences
...df2, works only for dataframes with identical rows and columns. In fact, all dataframes axes are compared with _indexed_same method, and exception is raised if differences found, even in columns/indices order.
If I got you right, you want not to find changes, but symmetric difference. For that, o...
C# code to validate email address
...e-mail addresses are more forgiving than you might first assume. These are all perfectly valid forms:
cog@wheel
"cogwheel the orange"@example.com
123@$.xyz
For most use cases, a false "invalid" is much worse for your users and future proofing than a false "valid". Here's an article that used to ...
Printing a variable memory address in swift
...er was quite old. Many of the methods it describes no longer work. Specifically .core cannot be accessed anymore.
However @drew's answer is correct and simple:
This is now part of the standard library: unsafeAddressOf.
So the answer to your questions is:
println(" str value \(str) has addre...
How to prevent a background process from being stopped after closing SSH client in Linux
...
I would recommend using GNU Screen. It allows you to disconnect from the server while all of your processes continue to run. I don't know how I lived without it before I knew it existed.
...
Maximum number of records in a MySQL database table
... The poster is not asking about numeric or any other data types. . I really do not understand how this can be flagged as a correct answer. Though I must admit that the question is ambiguous we should distinguish between PK data type and maximum number of rows for a table.
–...
How do Python functions handle the types of the parameters that you pass in?
...object has a type, every object knows its type, it's impossible to accidentally or deliberately use an object of a type "as if" it was an object of a different type, and all elementary operations on the object are delegated to its type.
This has nothing to do with names. A name in Python doesn't "...
Will Emacs make me a better programmer? [closed]
... who are merely good or competent will pick up an IDE and get to know it really well, and maybe do decently enough in it, but they'll restrict themselves to what the IDE provides for them. In other words, they adapt themselves to the IDE. The great programmers, on the other hand, will adapt their en...
Which way is best for creating an object in JavaScript? Is `var` necessary before an object property
...your example, Person (you should start the name with a capital letter) is called the constructor function. This is similar to classes in other OO languages.
Use way 2 if you only need one object of a kind (like a singleton). If you want this object to inherit from another one, then you have to use a...
back button callback in navigationController in iOS
...elegate if it should pop the top UINavigationItem by calling navigationBar(_:shouldPop:). UINavigationController actually implement this, but it doesn't publicly declare that it adopts UINavigationBarDelegate (why!?). To intercept this event, create a subclass of UINavigationController, declare its ...
Why compile Python code?
...ou invoke with python main.py is recompiled every time you run the script. All imported scripts will be compiled and stored on the disk.
Important addition by Ben Blank:
It's worth noting that while running a
compiled script has a faster startup
time (as it doesn't need to be
compiled), i...