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Generating random whole numbers in JavaScript in a specific range?
How can I generate random whole numbers between two specified variables in JavaScript, e.g. x = 4 and y = 8 would output any of 4, 5, 6, 7, 8 ?
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What is the best way to compute trending topics or tags?
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This problem calls for a z-score or standard score, which will take into account the historical average, as other people have mention, but also the standard deviation of this historical data, making it more robust than just using the average.
In your case a z-sc...
Are +0 and -0 the same?
Reading through the ECMAScript 5.1 specification , +0 and -0 are distinguished.
9 Answers
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How to use php serialize() and unserialize()
... means to put the structure into a "lower common denominator" that can be handled by things other than PHP, like databases, text files, sockets. The standard PHP function serialize is just a format to express such a thing, it serializes a data structure into a string representation that's unique to ...
How can we match a^n b^n with Java regex?
...a regex pattern to match anbn. It uses a positive lookahead for assertion, and one nested reference for "counting".
Rather than immediately giving out the pattern, this answer will guide readers through the process of deriving it. Various hints are given as the solution is slowly constructed. In thi...
Read an Excel file directly from a R script
... directly into R? Or should I first export the data to a text- or CSV file and import that file into R?
12 Answers
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Ukkonen's suffix tree algorithm in plain English
...st String Searching With Suffix Trees , but he glosses over various points and some aspects of the algorithm remain unclear.
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Why is SSE scalar sqrt(x) slower than rsqrt(x) * x?
I've been profiling some of our core math on an Intel Core Duo, and while looking at various approaches to square root I've noticed something odd: using the SSE scalar operations, it is faster to take a reciprocal square root and multiply it to get the sqrt, than it is to use the native sqrt opcode!...
How does PHP 'foreach' actually work?
Let me prefix this by saying that I know what foreach is, does and how to use it. This question concerns how it works under the bonnet, and I don't want any answers along the lines of "this is how you loop an array with foreach ".
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Is False == 0 and True == 1 an implementation detail or is it guaranteed by the language?
Is it guaranteed that False == 0 and True == 1 , in Python (assuming that they are not reassigned by the user)? For instance, is it in any way guaranteed that the following code will always produce the same results, whatever the version of Python (both existing and, likely, future ones)?
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