I am just not seeing this error kinda need an extra pair of eyes please (C++)

jus71n742 · 02-28-2009, 08:46 PM

trail.cpp

Code:

#include <cmath>
#include <iostream>
using namespace std;

int find(double, double);

int main(void){

        double num, pos;

        cout << "Please enter a positive integer and the number of";
        cout << "trailing digits:  ";

        cin >> pos >> num;

        find(pos,num);

}

find.cpp

Code:

#include <cmath>
#include <iostream>
using namespace std;

void find(double pos,double num){
        int trail;

        trail = pos % pow(10.0,num);

        cout << endl;
        cout << "The "<<num<<" trailing digits of "<<pos<<" are ";
        cout << trail<<".\n";

}

the error is: Line 19 is just below int main (void) in trail.cpp

Code:

find.cpp: In function ‘void find(double, double)’:
find.cpp:19: error: invalid operands of types ‘double’ and ‘double’ to binary ‘operator%’

I appreciate any help up front

fantas · 02-28-2009, 08:53 PM

In C/C++ there's no modulo operator defined for floating point values, but you have the option to use functions like fmod.

jus71n742 · 02-28-2009, 09:01 PM

so change doubles to int's and now that I think I really don't need to mod the pow*pow(10, num).
so it should work with

Code:

ans=num%divider ( changing nec variables)

fantas · 03-01-2009, 04:24 PM

For your basic experiments you'll just be fine with integers. It won't hurt though to also read up on the floating point data types as well. They certainly take a special place and require different handling than integers.