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Create Pandas DataFrame from a string
In order to test some functionality I would like to create a DataFrame from a string. Let's say my test data looks like:
...
Curious null-coalescing operator custom implicit conversion behaviour
...
return new C();
}
public static void Main() {
C? test = (X() ?? Y()) ?? Z();
}
}
This code will output:
X()
X()
A to B (0)
X()
X()
A to B (0)
B to C (0)
That made me think that the first part of each ?? coalesce expression is evaluated twice.
This code proved it:
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How do I share IntelliJ Run/Debug configurations between projects?
...uming others might as well.
That is, How to save unit and instrumentation test run configurations? I usually right-click on the test directory which brings up a menu with the option to Run whatever is in that directory. AndroidStudio then creates a run configuration on the fly and in the Run Config...
Switch on ranges of integers in JavaScript [duplicate]
... alert("9 to 11");
}
} else {
alert("not in range");
}
Speed test
I was curious about the overhead of using a switch instead of the simpler if...else..., so I put together a jsFiddle to examine it...
http://jsfiddle.net/17x9w1eL/
Chrome: switch was around 70% slower than if else
Fi...
Select multiple records based on list of Id's with linq
... .Contains took 2 minutes and 19 seconds! I used pure IEnumerable for this testing to prove my statement. If you use List instead of IEnumerable, .Where and .Contains will be faster. Anyway the difference is significant. The fastest .Where .Contains is with Set<>. All it depends on complexity ...
Should flux stores, or actions (or both) touch external services?
...ronous. This makes your store logic much easier to follow and very easy to test—just instantiate a store with some given state, send it an action, and check to see if the state changed as expected. Furthermore, one of the core concepts in flux is to prevent cascading dispatches and to prevent mult...
What's the difference between IComparable & IEquatable interfaces?
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IEquatable tests whether two objects are equal.
IComparable imposes a total ordering on the objects being compared.
For example, IEquatable would tell you that 5 is not equal to 7. IComparable would tell you that 5 comes before 7.
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Getting the IP address of the current machine using Java
...to-point IPv4 address.
In fact, the InetAddress API provides methods for testing for loopback, link local, site local, multicast and broadcast addresses. You can use these to sort out which of the IP addresses you get back is most appropriate.
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Read-only and non-computed variable properties in Swift
...r in Swift (cut&paste of your code, plus some modifications, I did not test it):
class Clock : NSObject {
var _hours: UInt = 0
var _minutes: UInt = 0
var _seconds: UInt = 0
var hours: UInt {
get {
return _hours
}
}
var minutes: UInt {
get {
r...
What is the difference between Class and Klass in ruby?
...n this results in an error, since you can't use class as a variable name.
test.rb:1: syntax error, unexpected kCLASS, expecting ')'
def show_methods(class)
^
test.rb:2: syntax error, unexpected ')'
puts Object.const_get(class).methods.inspect
To fix it, we'll u...