Check out this collection of random number generators from George Marsaglia. He’s a leading expert in random number generation, so I’d be confident using anything he recommends. The generators in that list are tiny, some requiring only a couple unsigned longs as state. Marsaglia’s generators are definitely “high quality” by your standards of long period … Read more
A jump table can be either an array of pointers to functions or an array of machine code jump instructions. If you have a relatively static set of functions (such as system calls or virtual functions for a class) then you can create this table once and call the functions using a simple index into … Read more
Thank you very much for your comments. I was able to reduce the delay to ~0.4ms. The command setserial(8) was referenced in the AEL manual. And bingo, I found the low_latency flag there with the following description: Minimize the receive latency of the serial device at the cost of greater CPU utilization. (Normally there is … Read more
Ah, the joys of bitwise arithmetic. A side effect of many division routines is the modulus – so in few cases should division actually be faster than modulus. I’m interested to see the source you got this information from. Processors with multipliers have interesting division routines using the multiplier, but you can get from division … Read more
I recently started reading Charles Petzold book titled Code, which so far covers exactly the kinds of things I assume you are curious about. But I have not gotten all the way through so thumb through the book first before buying/borrowing. This is my relatively short answer, not Petzolds…and hopefully in line with what you … Read more
The Modula-3 garbage collector needs to suspend pthreads at an arbitrary time, not just when they are waiting on a condition variable or mutex. It does it by registering a (Unix) signal handler that suspends the thread and then using pthread_kill to send a signal to the target thread. I think it works (it has … Read more
This might help: In-place matrix transposition. (You might also have to do some mirroring after the transposition, as rlbond mentions).
It wouldn’t. The two fundamental issues with global variables is simply cluttering the namespace, and the fact that “no one” has “control” over them (thus the potential collisions and conflict with multiple threads). The “globals are bad”, like pretty much every other computer programming idiom is a guideline, not a hard and fast rule. When … Read more
That depends on the exact “object-oriented” feature-set you want to have. If you need stuff like overloading and/or virtual methods, you probably need to include function pointers in structures: typedef struct { float (*computeArea)(const ShapeClass *shape); } ShapeClass; float shape_computeArea(const ShapeClass *shape) { return shape->computeArea(shape); } This would let you implement a class, by “inheriting” … Read more
When an exception occurs there will be time overhead which depends on how you implement your exception handling. But, being anecdotal, the severity of an event that should cause an exception will take just as much time to handle using any other method. Why not use the highly supported language based method of dealing with … Read more