Storing binary (boolean) matrices where each element is a byte (or worse, a 32 or 64 bit integer) is incredibly inefficient and wasteful, both in time and space. For example, a 10k square matrix requires 400Mb of RAM if stored as 32 bit int values. Binmat is a library that bit-packs these matrices so that this 10k square matrix requires just 12.5Mb (the minimum space possible). More than that, binmat takes advantage of extremely fast bit-operations when multiplying matrices. The usual series of multiplications and additions required to compute each element are replaced by bitwise AND and OR operations. Furthermore, on 64-bit hardware each bitwise operation can replace up to 64 multiplications or additions, reducing operations that can take hundreds of clock cycles down to just a single cycle. This gives rise to some very considerable performance increases, especially when taking the power of a matrix. Binary exponentiation is implemented to further improve the performance of higher matrix powers.
DVelum is a professional development platform which aims at automating routine development tasks and facilitates programming by means of a graphical interface. The platform simplifies and accelerates the development process and allows for concentrating directly on the business logic, aside from low-level problems. This is not another CMS or framework, it is a platform for the development of systems with a complex internal structure, such as eCommerce, CRM, WebScada, etc., while the development of simple sites with its help is as easy and pleasant.
Termdebug is a set of utilities for recording and replaying the input and output of terminal programs. Its main goal is to aid in developing and debugging terminal programs. Other programs such as termrec/termplay, nethack-recorder/player, and script/scriptreplay only record the output. However, when debugging an interactive terminal program, the input is often as important as the output.
halttimer waits for LIRC events or SIGUSR1 and sets a timer which will initiate the shutdown sequence (via "sudo halt" by default) when the time is up. The timer's timeout decreases with each keypress by a specified amount of time. Visualization is done using an on-screen-display (OSD).
SQLet allows you to directly execute SQL on multiple text files, right from the Linux commandline. In one single command, you can read in text files (with or without header lines) and perform arbitrary select statements, including joins over several files. SQLet can thus replace awk or grep in some instances.