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Differences between “BEGIN RSA PRIVATE KEY” and “BEGIN PRIVATE KEY”
Hi I was writing a program that imports private keys from a .pem file and create a private key object to use it later..
the problem I have faced is that some pem files header begin with
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Selecting only numeric columns from a data frame
...list-apply functions:
nums <- unlist(lapply(x, is.numeric))
Then standard subsetting
x[ , nums]
## don't use sapply, even though it's less code
## nums <- sapply(x, is.numeric)
For a more idiomatic modern R I'd now recommend
x[ , purrr::map_lgl(x, is.numeric)]
Less codey, less ref...
ScalaTest in sbt: is there a way to run a single test without tags?
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Just to clarify, if you run it from the command line, it should be as single argument: sbt "testOnly *MySuite -- -z foo"
– Sogartar
Jan 11 '17 at 17:17
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How does MySQL process ORDER BY and LIMIT in a query?
...ments, the first argument specifies the offset of the first row to return, and the second specifies the maximum number of rows to return. The offset of the initial row is 0 (not 1):
SELECT * FROM tbl LIMIT 5,10; # Retrieve rows 6-15
To retrieve all rows from a certain offset up to the end of the...
Programmer Puzzle: Encoding a chess board state throughout a game
...e: I liked this topic so much I wrote Programming Puzzles, Chess Positions and Huffman Coding. If you read through this I've determined that the only way to store a complete game state is by storing a complete list of moves. Read on for why. So I use a slightly simplified version of the problem for ...
JavaScript: clone a function
...t wrap twice when called twice, but otherwise, ok.
– Andrey Shchekin
Dec 2 '09 at 19:25
apply is used to pass the argu...
What is SuppressWarnings (“unchecked”) in Java?
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Sometimes Java generics just doesn't let you do what you want to, and you need to effectively tell the compiler that what you're doing really will be legal at execution time.
I usually find this a pain when I'm mocking a generic interface, but there are other examples too. It's usually wor...
How to remove item from list in C#?
...s {
public int ID; public string FirstName; public string LastName;
}
and assigned some values to results as follows:
var results=new List<myClass> {
new myClass() { ID=1, FirstName="Bill", LastName="Smith" },
new myClass() { ID=2, FirstName="John", LastName="Wilson" },
new ...
Fastest way to find second (third…) highest/lowest value in vector or column
R offers max and min, but I do not see a really fast way to find another value in the order, apart from sorting the whole vector and then picking a value x from this vector.
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Regex doesn't work in String.matches()
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Welcome to Java's misnamed .matches() method... It tries and matches ALL the input. Unfortunately, other languages have followed suit :(
If you want to see if the regex matches an input text, use a Pattern, a Matcher and the .find() method of the matcher:
Pattern p = Pattern.comp...