Thread: floats

  1. #1
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    floats

    Please...

    is this sentence right?
    whats wrong here?

    i have 2 floats, and i want to operate, like an exponencial, or
    float 1 elevated to float2.

    example:

    float1=2
    float2=1.5

    float3 = float1^float2;

    is this right/possible? my compiler says thats a wrong sentence, but, how is the right way to do that?

    Thanks!!!

  2. #2
    Just because ygfperson's Avatar
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    float3 = float1^float2;

    is this right/possible? my compiler says thats a wrong sentence, but, how is the right way to do that?
    Just FYI, bitwise operations are only possible on integral types (int, long, char, short int).

  3. #3
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    floats again

    Could someone help me?

    Imagine that i have the case:

    int a = 2;

    int b = 2;

    int c;

    so, once c = a^b, then c = 4, right?

    but, when i make this-like operation with two floats, like:

    float a = 1.25;
    float b = 2.53;
    float c;

    and i want the same thing, like

    c = a^b;

    but with floats it does not work.

    so, is there any way to do that? i tried to use pow(), but i`ve had the message: function has no prototype, even including the math.h library. is there any other way???

    Please....

    Thanks in advance

  4. #4
    Just Lurking Dave_Sinkula's Avatar
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    >so, once c = a^b, then c = 4, right?

    No, 2 XORed with 2 is 0. In C, you get x to the power of y with the pow() function.
    Code:
    #include <stdio.h> 
    #include <math.h> 
    
    int main(void)
    {
       double x = 2.0, y = 1.5, z = pow(x,y);
       printf("pow(%g,%g) = %g\n", x, y, z);
       return 0; 
    } 
    
    /* my output
    pow(2,1.5) = 2.82843
    */
    7. It is easier to write an incorrect program than understand a correct one.
    40. There are two ways to write error-free programs; only the third one works.*

  5. #5
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    Thise code works just fine for me using cygwin.

    Code:
    #include <math.h>
    #include <stdio.h>
    
    int main()
    {
    	double x = 1.25;
    	double y = 2.22;
    	
    	printf("x raised to y is %f\n", pow(x,y));
    
    	return 0;
    }
    For future reference, the ^ symbol in C means bitwise exclusive OR and not exponentiation.

    Also, why create another thread on the exact same topic?
    Last edited by damonbrinkley; 07-07-2003 at 08:14 PM.
    Wandering aimlessly through C.....

    http://dbrink.phpwebhosting.com

  6. #6
    ATH0 quzah's Avatar
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    Originally posted by damonbrinkley
    Also, why create another thread on the exact same topic?
    Because they either:
    a) Didn't care enough to actually read their post again.
    b) Didn't like the answer they got in the first thread, telling them the exact same thing they were told in this one.

    Quzah.
    Hope is the first step on the road to disappointment.

  7. #7
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    not really...

    Not really like that....i`ve made that (2 questions of the exact same topic) just because i thought the other one was old (i posted it on the morning), and i thought the most actual were read first. (at least, this is the way other discussion boards i know work).

    But i`m taking the way of this one. And i dont want to be boring, but u really are helpful, and all i have to say is thank you all....

    you are helping me to turn myself in a person which tomorrow will be here helping other dummies =)

    so, i`ll be less repetitive, ok =)

    thanks, and sorry!

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