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R Programming. R Statistical Software. R. Using Buffered I/O (Windows Driver Kit) The I/O manager determines that an I/O operation is using buffered I/O as follows: The following figure illustrates how the I/O manager sets up an IRP_MJ_READ request for a transfer operation that uses buffered I/O.

Using Buffered I/O (Windows Driver Kit)

The figure shows an overview of how drivers can use the SystemBuffer pointer in the IRP to transfer data for a read request, when a driver has ORed the device object's Flags with DO_BUFFERED_IO: Drivers that transfer large amounts of data at a time, in particular, drivers that do multipage transfers, should not attempt to use buffered I/O. As the system runs, nonpaged pool can become fragmented so that the I/O manager cannot allocate large, contiguous system-space buffers to send in IRPs for such a driver. Mark Watson, Ruby and Java Consultant and Author. Package Index : SIP 4.12.1. Package Index > SIP > 4.15.5 Not Logged In Python extension module generator for C and C++ libraries SIP is an extension module generator similar to SWIG but is specifically designed for creating Python modules.

Package Index : SIP 4.12.1

Generated code can be compiled for Python v2 and v3. Accurately computing running variance. The most direct way of computing sample variance or standard deviation can have severe numerical problems.

Accurately computing running variance

Mathematically, sample variance can be computed as follows. The most obvious way to compute variance then would be to have two sums: one to accumulate the sum of the x's and another to accumulate the sums of the squares of the x's. If the x's are large and the differences between them small, direct evaluation of the equation above would require computing a small number as the difference of two large numbers, a red flag for numerical computing. The loss of precision can be so bad that the expression above evaluates to a negative number even though variance is always positive. See Comparing three methods of computing standard deviation for examples of just how bad the above formula can be.

There is a way to compute variance that is more accurate and is guaranteed to always give positive results. This better way of computing variance goes back to a 1962 paper by B. Machine Learning. Shared Libraries. Shared libraries are libraries that are loaded by programs when they start.

Shared Libraries

When a shared library is installed properly, all programs that start afterwards automatically use the new shared library. It's actually much more flexible and sophisticated than this, because the approach used by Linux permits you to: update libraries and still support programs that want to use older, non-backward-compatible versions of those libraries;override specific libraries or even specific functions in a library when executing a particular all this while programs are running using existing libraries. 3.1. Conventions For shared libraries to support all of these desired properties, a number of conventions and guidelines must be followed. Functional Programming. BrainSCANr. Dr. Dobb's and Intel Go Parallel Programming.

Web Programming

C# C++ C. BST. Fortran. Scripting. Tek-Tips Forums. Objects, Identity, and Concept-Formation « Apocalisp. Coming from a background in Pascal and C, during the 1990s, like most others, I became infatuated with Object-Oriented programming.

Objects, Identity, and Concept-Formation « Apocalisp

Performance difference between C++ and C# for mathematics. Online IDE & Debugging Tool >> C/C++, Java, PHP, Python, Perl and 40+ compilers and intepreters. Douglas Rushkoff: Why Johnny Can't Program: A New Medium Requires A New Literacy. Ask any kid what Facebook is for and he'll tell you it's there to help him make friends.

Douglas Rushkoff: Why Johnny Can't Program: A New Medium Requires A New Literacy

What else could he think? It's how he *does* make friends. He has no idea the real purpose of the software, and the people coding it, is to monetize his relationships. He isn't even aware of those people, the program, or their purpose. The kids I celebrated in my early books as "digital natives" capable of seeing through all efforts of big media and marketing have actually proven *less* capable of discerning the integrity of the sources they read and the intentions of the programs they use. Amazingly, America - the birthplace of the Internet - is the only developed nation that does not teach programming in its public schools. Just last year, while researching a book on America's digital illiteracy, I met with the Air Force General then in charge of America's cybercommand. When human beings acquired language, we learned not just how to listen but how to speak. All systems have embedded purposes. The Pragmatic Bookshelf. That C has won the end-user practicality battle is obvious to everyone except developers.

The Pragmatic Bookshelf

The year is 1978, and the first wave of punk rock is reaching its nihilistic peak with infamous U.K. band the Sex Pistols touring the United States and promptly breaking up by the time they reach the West Coast. Elsewhere, Brian Kernighan and Dennis Ritchie are putting the finishing touches on their book The C Programming Language, which will become the de facto standardization of the language for years. 10 Reasons Why People Initially Suck at Programming. Initially everyone sucks at programming.

10 Reasons Why People Initially Suck at Programming

So we decided to compile a list that identifies reasons and advice to improve your programming skills.