geography_centroid_from_wpoints()

LWPOINT * geography_centroid_from_wpoints	(	const uint32_t	srid,
		const POINT3DM *	points,
		const uint32_t	size
	)

Convert lat-lon-points to x-y-z-coordinates, calculate a weighted average point and return lat-lon-coordinated.

Definition at line 180 of file geography_centroid.c.

{
    double_t x_sum = 0;
    double_t y_sum = 0;
    double_t z_sum = 0;
    double_t weight_sum = 0;
 
    double_t weight = 1;
    POINT3D* point;
 
        uint32_t i;
        for (i = 0; i < size; i++ )
    {
                point = lonlat_to_cart(points[i].x, points[i].y);
        weight = points[i].m;
 
        x_sum += point->x * weight;
        y_sum += point->y * weight;
        z_sum += point->z * weight;
 
        weight_sum += weight;
 
                lwfree(point);
    }
 
    return cart_to_lwpoint(x_sum, y_sum, z_sum, weight_sum, srid);
}

References cart_to_lwpoint(), lonlat_to_cart(), lwfree(), POINT3DM::m, POINT3D::x, pixval::x, POINT3D::y, pixval::y, and POINT3D::z.

Referenced by geography_centroid(), geography_centroid_from_mline(), and geography_centroid_from_mpoly().

Here is the call graph for this function:

Here is the caller graph for this function: