Category Archives: PHP

Computer Algorithms: Data Compression with Diagram Encoding and Pattern Substitution

Posted on January 23, 2012 by Stoimen

Overview Two variants of run-length encoding are the diagram encoding and the pattern substitution algorithms. The diagram encoding is actually a very simple algorithm. Unlike run-length encoding, where the input stream must consists of many repeating elements, as “aaaaaaaa” for … Continue reading →

Posted in algorithms, PHP | Tagged Coding theory, Computer file formats, Computer science, Computing, conventional compressing tool, Data compression, html, Information theory, Lossy compression, pattern substitution algorithm, pattern substitution algorithms, Pattern Substitution The pattern substitution algorithm, PHP, Run-length encoding, web hosting | Leave a comment

Computer Algorithms: Data Compression with Bitmaps

Posted on January 16, 2012 by Stoimen

Overview In my previous post we saw how to compress data consisting of very long runs of repeating elements. This type of compression is known as “run-length encoding” and can be very handy when transferring data with no loss. The … Continue reading →

Posted in algorithms, PHP | Tagged Algorithm, bitmap, bitmap compressing algorithm, Bzip2, Coding theory, Computing, Data compression, gif, Graphics file formats, image compression, Information theory, JSON, Lossless data compression, PHP, Run-length encoding, Technology/Internet | Leave a comment

Computer Algorithms: Data Compression with Run-length Encoding

Posted on January 9, 2012 by Stoimen

Introduction No matter how fast today’s computers and networks are, the users will constantly need faster and faster services. To reduce the volume of the transferred data we usually use some sort of compression. That is why this computer sciences … Continue reading →

Posted in algorithms, PHP | Tagged ajax, Algorithmic efficiency, binary search, Bzip2, Data compression, data compression algorithm, data compression algorithms, faster services, Google Inc., JSON, Lossless data compression, lossless data compression algorithm, Lossy compression, PHP, programmer, run-length algorithm, Run-length encoding, search algorithms, Technology/Internet, This algorithm, virtual machine, web server | 1 Comment

PHP Performance: Bitwise Division

Posted on January 5, 2012 by Stoimen

Recently I wrote about binary search and then I said that in some languages, like PHP, bitwise division by two is not faster than the typical “/” operator. However I decided to make some experiments and here are the results. … Continue reading →

Posted in PHP, web development | Tagged bitwise operation, bitwise operators, division, performance tests, PHP, php performance, research | 1 Comment

Computer Algorithms: Interpolation Search

Posted on January 2, 2012 by Stoimen

Overview I wrote about binary search in my previous post, which is indeed one very fast searching algorithm, but in some cases we can achieve even faster results. Such an algorithm is the “interpolation search” – perhaps the most interesting … Continue reading →

Posted in algorithms, PHP | Tagged Algorithm, binary search, Binary search algorithm, Binary search tree, even binary search, Interpolation, Interpolation search, interpolation search algorithm, Jump search, Logarithm, PHP, search algorithm, search algorithms, searching algorithms, Selection algorithm, Technology/Internet | 2 Comments