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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...
How do I run msbuild from the command line using Windows SDK 7.1?
I'm setting up .NET 4.0 support on our CI server. I've installed .NET 4.0, and the .NET tools from the Windows 7.1 SDK.
7 A...
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.
...
How do I create delegates in Objective-C?
...ign it as the web view's delegate:
MyClass *instanceOfMyClass = [[MyClass alloc] init];
myWebView.delegate = instanceOfMyClass;
On the UIWebView side, it probably has code similar to this to see if the delegate responds to the webViewDidStartLoad: message using respondsToSelector: and send it if ...
Setting up two different static directories in node.js Express framework
...nal (first) parameter to use() like so:
app.use("/public", express.static(__dirname + "/public"));
app.use("/public2", express.static(__dirname + "/public2"));
That way you get two different directories on the web that mirror your local directories, not one url path that fails over between two lo...
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...
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 ...
Can dplyr package be used for conditional mutating?
...and the conditions (except for the default value of NA at the end) are mutually exclusive, as is the case in the question, then we can use an arithmetic expression such that each term is multiplied by the desired result using na_if at the end to replace 0 with NA.
df %>%
mutate(g = 2 * (a == 2 ...
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 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 "...