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Initializing a list to a known number of elements in Python [duplicate]
Right now I am using a list, and was expecting something like:
9 Answers
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Is there a standard sign function (signum, sgn) in C/C++?
I want a function that returns -1 for negative numbers and +1 for positive numbers.
http://en.wikipedia.org/wiki/Sign_function
It's easy enough to write my own, but it seems like something that ought to be in a standard library somewhere.
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Synchronizing a local Git repository with a remote one
...er in these repositories, we override the local ones with the remote ones, and if there are files in local repositories that do not exist in the remote, the local files get removed.
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What is the difference between HTTP status code 200 (cache) vs status code 304?
... cache them (e.g. future-dated Expires or Cache-Control: max-age headers), and that at the time you triggered the new request, those cached objects were still stored in local cache and had not yet expired.
304s, on the other hand, are the response of the server after the browser has checked if a fi...
What is in your Mathematica tool bag? [closed]
...ned this before, but the tool I find most useful is an application of Reap and Sow which mimics/extends the behavior of GatherBy:
SelectEquivalents[x_List,f_:Identity, g_:Identity, h_:(#2&)]:=
Reap[Sow[g[#],{f[#]}]&/@x, _, h][[2]];
This allows me to group lists by any criteria and tran...
Can code that is valid in both C and C++ produce different behavior when compiled in each language?
C and C++ have many differences, and not all valid C code is valid C++ code.
(By "valid" I mean standard code with defined behavior, i.e. not implementation-specific/undefined/etc.)
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Can every recursion be converted into iteration?
...u always turn a recursive function into an iterative one? Yes, absolutely, and the Church-Turing thesis proves it if memory serves. In lay terms, it states that what is computable by recursive functions is computable by an iterative model (such as the Turing machine) and vice versa. The thesis does ...
Can a foreign key be NULL and/or duplicate?
...als. Suppose further that each proposal only has one sales person assigned and one client. So your proposal table would have two foreign keys, one with the client ID and one with the sales rep ID. However, at the time the record is created, a sales rep is not always assigned (because no one is fre...
Do htmlspecialchars and mysql_real_escape_string keep my PHP code safe from injection?
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When it comes to database queries, always try and use prepared parameterised queries. The mysqli and PDO libraries support this. This is infinitely safer than using escaping functions such as mysql_real_escape_string.
Yes, mysql_real_escape_string is effectively just a ...
What are the obj and bin folders (created by Visual Studio) used for?
I created a new project in Visual Studio 2010 and noticed that there are now two new folders named obj and bin in my project directory.
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