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« Cache-oblivious algorithms take into account something that has been ignored in all the lectures so far, particularly, the multilevel memory hierarchy of modern computers. Retrieving items from various levels of memory and cache make up a dominant factor of running time, so for speed it is crucial to minimize these costs. The main idea of cache-oblivious algorithms is to achieve optimal use of caches on all levels of a memory hierarchy without knowledge of their size. »

« The core of STXXL is an implementation of the C++ standard template library STL for external memory (out-of-core) computations, i. e., STXXL implements containers and algorithms that can process huge volumes of data that only fit on disks. »

OpenCV is a library of computer vision algorithms, picture processing algorithms, and general-purpose numerical algorithms. The library is written in C/C++ and is free both for academic and commercial use, as it is distributed under the BSD license. The time has come to check this library with the PVS-Studio code analyzer. OpenCV is a large library. It contains more than 2500 optimized algorithms and consists of more than 1 million code lines. Cyclomatic complexity of the most complex function cv::cvtColor() is 415. It is no wonder that we have found quite many errors and questionable fragments in its code. However, the size of the source code taken into account, we may call this library a high quality one.

The Archive of Interesting Code is an (ambitious) effort on my part to research, intuit, and code up every interesting algorithm and data structure ever invented. In doing so, I hope both to learn the mathematical techniques that power these technologies and to improve my skills as a programmer. The examples on this site are in a variety of languages. I generally prefer to use C++ for algorithms, since the STL provides a great framework for expressing algorithms that work on a variety of data types. I code up most data structures in Java, both because the Collections framework allows them to be integrated in seamlessly with other applications and because automatic garbage collection simplifies some of the resource management. Every now and then I'll find an algorithm or data structure that is best represented in a different language like Haskell, in which case I'll forgo my usual language conventions.

« A little-known fact about RFC 2617 is that HTTP authentication is extensible. The RFC defines and Apache has modules for Basic and Digest authentication, but developers are free to define different algorithms for use within the HTTP authentication framework, and servers are free to insist that clients support those algorithms if they want access to the server's resources. »

A description of the reservoir sampling algorithm for randomly selecting N items from a collection of unknown size in a single iteration ... including a discussion of how to deal with weighted inputs.

Outsourcing is great, but it may not be appropriate for certain functions. The Rule of Thumb is, 'If something comes in the first few sentences of your pitch, You probably don't want to outsource it.' For instance, Google's pitch is that its search algorithm provides better results than everyone else's. It is their core offering and prime differentiating factor. Hence, they probably should not outsource the development of the "PageRank" search algorithm. Now, even google may decide to outsource some non-­‐core software such as the front-­‐end work for the android web page or sales support CRM for their Adwords team. In fact, they do. According to Google, a business should "Eliminate, automate or outsource any of the non-­‐value transactional work-­‐ it has really freed up ourselves, and it is a never-­‐ending exercise to constantly refine that."

non preemptive priority based algorithm used in schdeuling process execution by operating system

AutoMapper uses a fluent configuration API to define an object-object mapping strategy. AutoMapper uses a convention-based matching algorithm to match up source to destination values.

AutoMapper uses a fluent configuration API to define an object-object mapping strategy. AutoMapper uses a convention-based matching algorithm to match up source to destination values.

"The Watchmaker Framework is an extensible, high-performance, object-oriented framework for implementing platform-independent evolutionary/genetic algorithms in Java. "

There is no fragment in program code where you cannot make mistakes. You may actually make them in very simple fragments. While programmers have worked out the habit of testing algorithms, data exchange mechanisms and interfaces, it's much worse concerning security testing. It is often implemented on the leftover principle. A programmer is thinking: "I just write a couple of lines now, and everything will be ok. And I don't even need to test it. The code is too simple to make a mistake there!". That's not right. Since you're working on security and writing some code for this purpose, test it as carefully!

Quite often we come across a requirement where we may need to perform some sort of fuzzy string grouping or data correlation. For example, we may want to correlate the customer records of a database by identifying records that are similar but not necessarily exactly the same (due to spelling mistakes for example). Obviously a simple group by, will not successfully group such data. We will need to employ what is commonly referred to as a distance algorithm or a string metric in order to determine how close 2 string values are.

Infer.NET is a .NET framework for machine learning. It provides state-of-the-art message-passing algorithms and statistical routines for performing Bayesian inference.

"I don't know why I did it, but I decided to translate the Perl module Algorithm::Diff into C#, since there aren't any C# libraries yet for finding the differences between two lists."

AutoMapper uses a fluent configuration API to define an object-object mapping strategy. AutoMapper uses a convention-based matching algorithm to match up source to destination values. It flattens as it maps to make it easy to use for converting your Model into a ViewModule or Data Transfer Object (DTO)..