How can I write real-time calculater _

Jun 12, 2020 at 3:41pm
Can I write real-time calculater with c programming ?

Last edited on Jun 13, 2020 at 9:01am
Jun 12, 2020 at 4:20pm
You should know by now that just posting your homework and expecting a complete answer on a plate just isn't going to work.

Make an effort first.
Jun 12, 2020 at 4:23pm
What does it mean to calculate something in real-time? Are there turn-based calculators?
Jun 12, 2020 at 5:02pm
f is the only one you can do better than the built in language. the built in one does too much for integers, so an optimized integer version is worth writing; there are several examples on here. All the others are on the cpu circuits and too fast to try to beat out with code.

an example I played with a few years back. you can remove the higher powers for even more speed if not needed; all they are good for is like 2^60 type values, you can probably stop at 16 for most practical uses. (16 gets you x^31 or lower powers).

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long long ipow(long long p, unsigned long long e) 
{ 
  const long long one = 1;
  const long long *lut[2] = {&p,&one};
  register long long result = 1;
    result *= lut[!(e&1)][0]; p *= p;
	result *= lut[!(e&2)][0]; p *= p;
	result *= lut[!(e&4)][0]; p *= p;
	result *= lut[!(e&8)][0]; p *= p;
	result *= lut[!(e&16)][0]; p *= p;
	result *= lut[!(e&32)][0]; p *= p;
	result *= lut[!(e&64)][0]; 	
	return result;
}


the same code can be used for doubles to integer powers.
if you want double powers, use the built in one, then you need the extra steps that it does.
Last edited on Jun 12, 2020 at 5:48pm
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