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Test whether a Ruby class is a subclass of another class
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2 Answers
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Does “\d” in regex mean a digit?
I found that in 123 , \d matches 1 and 3 but not 2 . I was wondering if \d matches a digit satisfying what kind of requirement? I am talking about Python style regex.
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Easiest way to convert int to string in C++
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28 Answers
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Merging two arrays in .NET
Is there a built in function in .NET 2.0 that will take two arrays and merge them into one array?
21 Answers
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What does $_ mean in PowerShell?
... in the pipe line, which is called $PSItem in Powershell 3 and newer.
1,2,3 | %{ write-host $_ }
or
1,2,3 | %{ write-host $PSItem }
For example in the above code the %{} block is called for every value in the array. The $_ or $PSItem variable will contain the current value.
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Can I read the hash portion of the URL on my server-side application (PHP, Ruby, Python, etc.)?
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12 Answers
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Speed up the loop operation in R
...possible. I took your function, change indexing and here version_A
dayloop2_A <- function(temp){
res <- numeric(nrow(temp))
for (i in 1:nrow(temp)){
res[i] <- i
if (i > 1) {
if ((temp[i,6] == temp[i-1,6]) & (temp[i,3] == temp[i-1,...
How many bytes in a JavaScript string?
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String values are not implementation dependent, according the ECMA-262 3rd Edition Specification, each character represents a single 16-bit unit of UTF-16 text:
4.3.16 String Value
A string value is a member of the type String and is a
finite ordered sequence of zero or
more 16-bit unsigned...
Create numpy matrix filled with NaNs
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You rarely need loops for vector operations in numpy.
You can create an uninitialized array an...