Register to reply

Hi-prec math for visual studio c#?

by devronious
Tags: hiprec, math, studio, visual
Share this thread:
devronious
#1
Jul23-08, 12:41 AM
P: 7
Is there a Hi-prec math for visual studio c#?

Thanks in advance,

Devin
Phys.Org News Partner Science news on Phys.org
New type of solar concentrator desn't block the view
Researchers demonstrate ultra low-field nuclear magnetic resonance using Earth's magnetic field
Asian inventions dominate energy storage systems
CRGreathouse
#2
Jul23-08, 09:02 AM
Sci Advisor
HW Helper
P: 3,684
There's at least one commercial package out there, but it's not cheap:
http://www.extremeoptimization.com/

What are your needs? What does the library need to do, and how fast does it need to work? Are you just using big numbers, or are you doing matrices? Basic operations (+, -, *, /, %, ^), transcendental (sin, sinh, asin, exp, log, erf, gamma), or specialized (bessel, hypergeom, prime operations, etc.)? Integer or floating-point?
devronious
#3
Jul23-08, 10:12 AM
P: 7
I'm doing floating point with basic math ops, ie: +,-,*,/,^, sqrt

CRGreathouse
#4
Jul23-08, 10:27 AM
Sci Advisor
HW Helper
P: 3,684
Hi-prec math for visual studio c#?

Does it need to be fast? Is anything running in a tight loop, or are you just writing (say) a calculator where an extra millisecond won't hurt?
devronious
#5
Jul23-08, 12:12 PM
P: 7
Doesn't need to be fast.
CRGreathouse
#6
Jul23-08, 01:59 PM
Sci Advisor
HW Helper
P: 3,684
You could write your own, then, or have someone write it. Quick code:

class Bignum {
	protected ulong[] limb;
	public Bignum (long initialValue) {
		limb = new ulong[] {initialValue};
	}

	public Bignum (long[] initialValue) {
		Array.Copy(limb, initialValue, initialValue.Length);
	}

	public Bignum (string initialValue) {
		// Bad method, replace with a faster one if needed
		limb = new ulong[] {long.Parse(initialValue.Substring(0, 18))};
		for (int i = 18; i < initialValue.Length; ++i)
			limb = limb * 10 + long.Parse(initialValue[i]);
	}

	public Bignum (Bignum initialValue) {
		Array.Copy(limb, initialValue.limb, initialValue.limb.Length);
	}

	public static Bignum operator+ (Bignum a, Bignum b) {
		long carry = 0;
		int sz = Math.Max (a.limb.Length. b.limb.length);

		Bignum result = new Bignum(a);
		for (int i = 0; i < sz; ++i) {
			long o1 = result.limb[i];
			long o2 = b.limb[i];
			limb[i] += b.limb[i] + carry;
			if (result.limb[i] < o1 || result.limb[i] < o2)
				carry = 1;
			else
				carry = 0;
		}
		if (carry == 1) {
			Array.Copy(result.limb, result.limb, result.limb.Length + 1);
			result.limb[sz] = 1;
		}
		return result;
	}

	public static Bignum operator* (Bignum a, Bignum b) {
		// Code here
	}

	public static Bignum operator^ (Bignum a, uint b) {
		Bignum result = new Bignum(a);
		Bignum carry = new Bignum(0);
		while (b > 1) {
			if ((b&1) == 1)
				carry *= result;
			result *= result;
			b >>= 1;
		}
		return result * carry;
	}
}
I haven't compiled this (or even used an IDE) but this should be a good start. Subtraction is easy, multiplication not too hard, and division... well, code that as far as you need it. I decided to do the exponentiation so it wouldn't be too slow.
devronious
#7
Jul25-08, 09:44 AM
P: 7
Cool, thanks for your time, effort & code. I like your usage of binary ops.

-Devin


Register to reply

Related Discussions
C code in visual studio Programming & Computer Science 7
Stumped on Visual Studio / Visual Basic Programming & Computer Science 5
What is the difference between Visual Studio .Net 2005 and Visual Studio 2005? Computing & Technology 4
Visual Studio Computing & Technology 13