What do i use to exponetiate something?

I'm working on a program that I need to use this equation:
1/2^n where n is a for loop number going up to 8. what can i use instead of carrot (^) to square or exponetiate somthing?

Plz help,
Artanis

std::pow(double, double);

from <cmath>

i.e.

double result = std::pow(.5, n);

thanks, how could i have been so stupid, heh heh

well, you could also create you're own recursive function, but that isn't necessary... but i feel like it and i'm bored, so...

Code:

---

#include <iostream>
using namespace std;

double power(double,double);

int main()
{
    double number;
    double exp;

    ...
   
    cout<<"Answer: "<<power(number,exp);

    return 0;
}

double power(double number, double exp)
{
    if(exp>1)
          return number*power(number, exp-1);
    else
          return number;
}

---

there it is... although it only works for positive exponents...

in your power function you need to add...

Code:

---

else if(exp==0)
return 1;

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that's why i said positive ;-)

oops i didnt see that sorry :o :o

Although writing your own functions is the best exercise, and there's nothing more fun than creating a recursive function :) The built-in library functions are almost always better (bug-free, fool-proof, flexable, etc.)

And, a "simple" recursive function can't do this: pow(0.5, 2.4)... In fact, I don't know how to do that! Hmmm, I'd have to dig out my math books... must have something to do with summing exponents...

Quote:

---

Originally posted by DougDbug
And, a "simple" recursive function can't do this: pow(0.5, 2.4)... In fact, I don't know how to do that! Hmmm, I'd have to dig out my math books... must have something to do with summing exponents...

---

Raise 0.5 to the 24th power, and take the 10th root (or the 12th power and take the 5th root, etc.). Use your home-built recursive function for the raising, but alas the only way I ever figured out how to get roots (other than the square root) is std::pow...

well recursive functions are fun to write... kinda like linked lists... or am i just strange?

I wonder how difficult it would be to make our own exp function with inline assembly...Arn't their ASM commands to do logarithms? (I don't have any x86 reference manuals, otherwise I would look in those)

Wow, you all went so far off from my question... Though these inquires are intriguing. I say thanks to Zach L. I didn't have time to make a recursive function, though it almost came to that!