         let l7coef = 61.0 - 479.0 * t2 + 179.0 * (t2 * t2) - (t2 * t2 * t2)
         let l8coef = 1385.0 - 3111.0 * t2 + 543.0 * (t2 * t2) - (t2 * t2 * t2)
         
+        // Compute the ellipsoidal distance from the equator to a point at a given latitude in meters
         let arcLengthOfMeridian: (Double, UTMDatum) -> Double = { latitudeInRadians, datum in
             let equitorialRadus = datum.equitorialRadius
             let polarRadius = datum.polarRadius

    let northing: Double
    let easting: Double
    
    init(northing: Double, easting: Double) {
        self.northing = northing
        self.easting = easting
    }
    
    init(utmCoordinate: UTMCoordinate) {
        easting = (utmCoordinate.easting - 500000.0) / utmScaleFactor;
        northing = {
            /* If in southern hemisphere, adjust y accordingly. */
            if case .southern = utmCoordinate.hemisphere {
                return (utmCoordinate.northing - 10000000.0) / utmScaleFactor
            } else {
                return utmCoordinate.northing / utmScaleFactor
            }
        }()
    }
    

        return footprintLatitudeInRadians
    }
    
}
