expected primary expression
Hi, I'm having a problem with this code.
Basically, I get an error at line 63 expected primary-expression before "double" and also at line 63 expected `;' before "double"
The original problem computes the angle gamma, but I need to make the gamma computation into a function and then call that function to calculate it. Any info would be much appreciated!
Code:
/*------------------------------------------------------------*/
/* Program chapter4_3 */
/* */
/* This program determines the distance between two points */
/* that are specified with latitude and longitude values */
/* that are in the Northern Hemisphere. */
#include <stdio.h>
#include <math.h>
#define PI 3.141593
int main(void)
{
/* Declare variables and function prototype. */
double lat1, long1, lat2, long2;
double gc_distance(double lat1, double long1,
double lat2, double long2);
double angle(double x1, double y1, double z1,
double x2, double y2, double z2);
setbuf( stdout, 0); /* make stdout unbuffered */
/* Get locations of two points. */
printf("Enter latitude north and longitude west ");
printf("for location 1: \n");
scanf("%lf %lf",&lat1,&long1);
printf("Enter latitude north and longitude west ");
printf("for location 2: \n");
scanf("%lf %lf",&lat2,&long2);
/* Print great circle distance. */
printf("Great Circle Distance: %.0f miles \n",
gc_distance(lat1,long1,lat2,long2));
/* Exit program. */
return 0;
}
/*------------------------------------------------------------*/
/* This function computes the distance between two */
/* points using great circle distances. */
double gc_distance(double lat1, double long1,
double lat2, double long2)
{
/* Declare variables. */
double rho, phi, theta, gamma, dot, dist1, dist2,
x1, y1, z1, x2, y2, z2;
/* Convert latitude,longitude to rectangular coordinates. */
rho = 3960;
phi = (90 - lat1)*(PI/180.0);
theta = (360 - long1)*(PI/180.0);
x1 = rho*sin(phi)*cos(theta);
y1 = rho*sin(phi)*sin(theta);
z1 = rho*cos(phi);
phi = (90 - lat2)*(PI/180.0);
theta = (360 - long2)*(PI/180.0);
x2 = rho*sin(phi)*cos(theta);
y2 = rho*sin(phi)*sin(theta);
z2 = rho*cos(phi);
gamma = double angle(double x1, double y1, double z1,
double x2, double y2, double z2);
/* Compute angle between vectors.
dot = x1*x2 + y1*y2 + z1*z2;
dist1 = sqrt(x1*x1 + y1*y1 + z1*z1);
dist2 = sqrt(x2*x2 + y2*y2 + z2*z2);
gamma = acos(dot/(dist1*dist2)); */
/* Compute and return great circle distance. */
return gamma*rho;
}
/*------------------------------------------------------------*/
double angle(double x1, double y1, double z1,
double x2, double y2, double z2)
{
double dot, dist1, dist2, gamma1;
dot = x1*x2 + y1*y2 + z1*z2;
dist1 = sqrt(x1*x1 + y1*y1 + z1*z1);
dist2 = sqrt(x2*x2 + y2*y2 + z2*z2);
gamma1 = acos(dot/(dist1*dist2));
return gamma1;
}
