Thread: raising to a power

  1. #1
    Registered User
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    Question raising to a power

    Does anyone know of a way to raise a constant to a variable.
    Ex. 15 raised to the (xy)
    Im kinda new to this so any help would be much appreciated.

  2. #2
    Registered User
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    Code:
    #include <cmath>
    #include <iostream>
    
    int main(){
         int xy = 2;
         int x = pow(3, 4);   //this means 3 to the fourth
         int y = pow(15, xy); //15 to the xy
         return 0;
    }

  3. #3
    Banned master5001's Avatar
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    Within reason, you can also unroll the multiplications.

    Code:
    int x, y;
    x = pow(15, 3);  //this works
    y = 15*15*15;   //this is faster
    Of course with variable exponents you will need to use the pow() functions.

  4. #4
    Its not rocket science vasanth's Avatar
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    wll if you want to write a function then this is how it works




    Code:
    power(x,y)
    {
    
    double temp=1;
    for(int i=0;i<y+1;i++)
    {
    
    temp=temp*x;
    
    }
    
    return temp;
    }

  5. #5
    Code Monkey Davros's Avatar
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    >y = 15*15*15; //this is faster

    Maybe, but what about:

    3^25

    or

    7^2.6
    OS: Windows XP
    Compilers: MinGW (Code::Blocks), BCB 5

    BigAngryDog.com

  6. #6
    Just a Member ammar's Avatar
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    2^3 doesn't work with me!
    Maybe I need to overload it.

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