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[Pooch]

Hey guys, I am working on my first C++ program for school. For some reason I am getting the following error when I try to compile it:

`truncate' undeclared (first use this function)

Source:

#include <iostream>
#include <math.h>

using namespace std;

#define CENTIMETERS_IN_INCH 2.54
#define POUNDS_IN_KILOGRAM 2.2

int main() {
	double feet, inches, centimeters, weight_in_kg, weight_in_lbs;
	
	// get height in feet and inches
	cout << "Enter height (feet): ";
	cin >> feet;
	cout << "Enter (inches): ";
	cin >> inches;
	
	// convert feet and inches into centimeters
	centimeters = ((12 * feet) + inches) * CENTIMETERS_IN_INCH;
	
	// round 2 decimal places and truncate
	centimeters = truncate(centimeters);
	
	printf("Someone that is %g' %g\" would be %g cm tall", feet, inches, centimeters);
	
	// weights for bmi of 18.5
	weight_in_kg = truncate(18.5 * centimeters);
	weight_in_lbs = round(weight_in_kg * POUNDS_IN_KILOGRAM);
	
	printf("18.5 BMI would correspond to about %g kg or %g lbs", weight_in_kg, weight_in_lbs);
	
	// weights for bmi of 25
	weight_in_kg = truncate(25 * centimeters);
	weight_in_lbs = round(weight_in_kg * POUNDS_IN_KILOGRAM);
	
	printf("25.0 BMI would correspond to about %g kg or %g lbs", weight_in_kg, weight_in_lbs);
	
	// pause output
	cin >> feet;
	
	return 0;
}

// round result
double round(double d) {
   return floor(d + 0.5);
}

// round and truncate to 1 decimal place
double truncate(double d) {
   return round(double * 10) / 10;
}

Any help would be appreciated. Thanks.

[rc69]

C/C++ cares about the order in which you declare things. A function/variable must be declared before it is referenced (it can be defined elsewhere though).

Ref: http://www.cplusplus...ons2/#declaring