Basic floating point arithmetic not working...

This is a discussion on Basic floating point arithmetic not working... within the C++ Programming forums, part of the General Programming Boards category; Hello, I am trying to run the following code (which is part of a larger program): Code: #include <iostream> #include ...

  1. #1
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    Basic floating point arithmetic not working...

    Hello,

    I am trying to run the following code (which is part of a larger program):

    Code:
    #include <iostream>
    #include <math.h>
    #include <stdio.h>
    #include <stdlib.h>
    #include <malloc.h>
    #include <time.h>
    #include <fstream>
    #define rand01 (0.9999999*double(rand())/RAND_MAX) 
    				
    #define getrandom(max1) (((rand())%(max1))) // random integer between 0 and max-1
    	  
    using namespace std;
    
    int main()
    {
    	double result;
    	int sec = 2;
    	int t = 10;
     	result= 2.0*3.14*(46/1000)*(sec*1000.0+t);
    
    	cout << result << "\n";
    
    	return 0;
    }

    My output for result is "0." This is incorrect. Anyone have any ideas?

    Thanks.

  2. #2
    C++ Witch laserlight's Avatar
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    Note that due to integer division, the result of (46/1000) is 0.
    Quote Originally Posted by Bjarne Stroustrup (2000-10-14)
    I get maybe two dozen requests for help with some sort of programming or design problem every day. Most have more sense than to send me hundreds of lines of code. If they do, I ask them to find the smallest example that exhibits the problem and send me that. Mostly, they then find the error themselves. "Finding the smallest program that demonstrates the error" is a powerful debugging tool.
    Look up a C++ Reference and learn How To Ask Questions The Smart Way

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    Thanks

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