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What is the easiest way in C# to trim a newline off of a string?
...impression \n was not a white space but it is and .TrimEnd and .Trim clear all white space characters natively
– David Carrigan
May 13 '15 at 20:46
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Convert data.frame column to a vector?
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You do not need as.vector(), but you do need correct indexing: avector <- aframe[ , "a2"]
The one other thing to be aware of is the drop=FALSE option to [:
R> aframe <- data.frame(a1=c1:5, a2=6:10, a3=11:15)
R> aframe
a1 a2 a3
1 1 6 11
2 2 7 12
3 3 8 13
4 ...
Are soft deletes a good idea? [duplicate]
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Also worth mentioning: a UNIQUE index in combination with soft deletes can make for a mess. E.g. trying to register a deleted username will fail, even though it is not in use.
– Danny Beckett
Jul 13 '13 at 21:38
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C++ Best way to get integer division and remainder
... experiment with g++ 6.3.0 on x86_64 revealed that with no optimization at all, you get two idivl instructions, but with -O1 or greater, you get one. As the manual says, “Without any optimization option … Statements are independent”.
– Tom Zych
Oct 15 '17...
Number of lines in a file in Java
...getLineNumber() + 1; // +1 because line index starts at 0
}
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Select random lines from a file
... @MonaJalal nope just faster, since it doesn't have to compare lines at all.
– rogerdpack
May 15 '17 at 17:20
Does ...
Setting a property by reflection with a string value
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You can use Convert.ChangeType() - It allows you to use runtime information on any IConvertible type to change representation formats. Not all conversions are possible, though, and you may need to write special case logic if you want to support conversions from t...
Programmatically go back to the previous fragment in the backstack
...ening. In fragment example developer.android.com/training/basics/fragments/index.html they are not overiding onbackpressed event and yet they are able to backstack fragment. I have used trasaction.addToBackStack(null); but nothing happens. Can you explain why ?
– Murtaza K...
Difference between Divide and Conquer Algo and Dynamic Programming
... which is unnecassary.
The famous example Fibonacci numbers:
index: 1,2,3,4,5,6...
Fibonacci number: 1,1,2,3,5,8...
function F(n) {
if (n < 3)
return 1
else
return F(n-1) + F(n-2)
}
Let's run F(5):
F(5) = F(4) + F(3)
= {F(3)+F(2)} + {F(2)+F(1)}
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simple HTTP server in Java using only Java SE API
... GET/POST) in Java using just the Java SE API, without writing code to manually parse HTTP requests and manually format HTTP responses? The Java SE API nicely encapsulates the HTTP client functionality in HttpURLConnection, but is there an analog for HTTP server functionality?
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