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My Understanding of HTTP Polling, Long Polling, HTTP Streaming and WebSockets
I have read many posts on SO and the web regarding the keywords in my question title and learned a lot from them. Some of the questions I read are related to specific implementation challenges while others focus on general concepts. I just want to make sure I understood all of the concepts and the r...
How to read from a file or STDIN in Bash?
...e following Perl script ( my.pl ) can read from either the file on the command line args or from STDIN:
15 Answers
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Why does string::compare return an int?
...eturn an int instead of a smaller type like short or char ? My understanding is that this method only returns -1, 0 or 1.
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How do I check in JavaScript if a value exists at a certain array index?
... element with index i is defined to be part of the array if i is between 0 and array.length - 1 inclusive. If i is not in this range it's not in the array.
So by concept, arrays are linear, starting with zero and going to a maximum, without any mechanism for having "gaps" inside that range where n...
How can I quantify difference between two images?
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General idea
Option 1: Load both images as arrays (scipy.misc.imread) and calculate an element-wise (pixel-by-pixel) difference. Calculate the norm of the difference.
Option 2: Load both images. Calculate some feature vector for each of them (like a histogram). Calculate distance between featu...
Is it safe to check floating point values for equality to 0?
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It is safe to expect that the comparison will return true if and only if the double variable has a value of exactly 0.0 (which in your original code snippet is, of course, the case). This is consistent with the semantics of the == operator. a == b means "a is equal to b".
It is not sa...
How to remove an item for a OR'd enum?
...rses or 'flips' all bits for the given data type. As such, if you use the AND operator (&) with some value (let's call that value 'X') and the complement of one or more set bits (let's call those bits Q and their complement ~Q), the statement X & ~Q clears any bits that were set in Q from X...
What is “entropy and information gain”?
I am reading this book ( NLTK ) and it is confusing. Entropy is defined as :
7 Answers
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Undefined, unspecified and implementation-defined behavior
What is undefined behavior in C and C++? What about unspecified behavior and implementation-defined behavior? What is the difference between them?
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Is there an easy way to check the .NET Framework version?
... }
}
}
}
}
}
For .NET 4.5 and later
// Checking the version using >= will enable forward compatibility,
// however you should always compile your code on newer versions of
// the framework to ensure your app works the same.
private static string ...