src/projCode/Poly.php
protected function phi4z($eccent, $e0, $e1, $e2, $e3, $a, $b, &$c, $phi)
    {
        /*
        $sinphi;
        $sin2ph;
        $tanph;
        $ml;
        $mlp;
        $con1;
        $con2;
        $con3;
        $dphi;
        $i;
        */

        $phi = $a;
        for ($i = 1; $i <= 15; $i++) {
            $sinphi = sin( $phi );
            $tanphi = tan( $phi );
            $c = $tanphi * sqrt( 1.0 - $eccent * $sinphi * $sinphi );
            $sin2ph = sin( 2.0 * $phi );
            /*
              ml = e0 * *phi - e1 * sin2ph + e2 * sin (4.0 *  *phi);
              mlp = e0 - 2.0 * e1 * cos (2.0 *  *phi) + 4.0 * e2 *  cos (4.0 *  *phi);
             */
            $ml = $e0 * $phi - $e1 * $sin2ph + $e2 * sin( 4.0 * $phi ) - $e3 * sin( 6.0 * $phi );
            $mlp = $e0 - 2.0 * $e1 * cos( 2.0 * $phi ) + 4.0 * $e2 * cos( 4.0 * $phi ) - 6.0 * $e3 * cos( 6.0 * $phi );
            $con1 = 2.0 * $ml + $c * ($ml * $ml + $b) - 2.0 * $a * ($c * $ml + 1.0);
            $con2 = $eccent * $sin2ph * ($ml * $ml + $b - 2.0 * $a * $ml) / (2.0 * $c);
            $con3 = 2.0 * ($a - $ml) * ($c * $mlp - 2.0 / $sin2ph) - 2.0 * $mlp;
            $dphi = $con1 / ($con2 + $con3);
            $phi += $dphi;

            if ( abs( $dphi ) <= .0000000001 ) {
                return($phi);
            }
        }

        Proj4php::reportError('phi4z: No convergence');

        return null;
    }
protected function phi4z($eccent, $e0, $e1, $e2, $e3, $a, $b, &$c, $phi)
    {
        /*
        $sinphi;
        $sin2ph;
        $tanph;
        $ml;
        $mlp;
        $con1;
        $con2;
        $con3;
        $dphi;
        $i;
        */

        $phi = $a;
        for ($i = 1; $i <= 15; $i++) {
            $sinphi = sin( $phi );
            $tanphi = tan( $phi );
            $c = $tanphi * sqrt( 1.0 - $eccent * $sinphi * $sinphi );
            $sin2ph = sin( 2.0 * $phi );
            /*
              ml = e0 * *phi - e1 * sin2ph + e2 * sin (4.0 *  *phi);
              mlp = e0 - 2.0 * e1 * cos (2.0 *  *phi) + 4.0 * e2 *  cos (4.0 *  *phi);
             */
            $ml = $e0 * $phi - $e1 * $sin2ph + $e2 * sin( 4.0 * $phi ) - $e3 * sin( 6.0 * $phi );
            $mlp = $e0 - 2.0 * $e1 * cos( 2.0 * $phi ) + 4.0 * $e2 * cos( 4.0 * $phi ) - 6.0 * $e3 * cos( 6.0 * $phi );
            $con1 = 2.0 * $ml + $c * ($ml * $ml + $b) - 2.0 * $a * ($c * $ml + 1.0);
            $con2 = $eccent * $sin2ph * ($ml * $ml + $b - 2.0 * $a * $ml) / (2.0 * $c);
            $con3 = 2.0 * ($a - $ml) * ($c * $mlp - 2.0 / $sin2ph) - 2.0 * $mlp;
            $dphi = $con1 / ($con2 + $con3);
            $phi += $dphi;

            if ( abs( $dphi ) <= .0000000001 ) {
                return($phi);
            }
        }

        Proj4php::reportError('phi4z: No convergence');

        return null;
    }
protected function phi4z ( $ eccent , $ e0 , $ e1 , $ e2 , $ e3 , $ a , $ b , & $ c , $ phi ) { /*
        $sinphi;
        $sin2ph;
        $tanph;
        $ml;
        $mlp;
        $con1;
        $con2;
        $con3;
        $dphi;
        $i;
        */ $ phi = $ a ; for ( $ i = 1 ; $ i <= 15 ; $ i ++ ) { $ sinphi = sin ( $ phi ) ; $ tanphi = tan ( $ phi ) ; $ c = $ tanphi * sqrt ( 1.0 - $ eccent * $ sinphi * $ sinphi ) ; $ sin2ph = sin ( 2.0 * $ phi ) ; /*
              ml = e0 * *phi - e1 * sin2ph + e2 * sin (4.0 *  *phi);
              mlp = e0 - 2.0 * e1 * cos (2.0 *  *phi) + 4.0 * e2 *  cos (4.0 *  *phi);
             */ $ ml = $ e0 * $ phi - $ e1 * $ sin2ph + $ e2 * sin ( 4.0 * $ phi ) - $ e3 * sin ( 6.0 * $ phi ) ; $ mlp = $ e0 - 2.0 * $ e1 * cos ( 2.0 * $ phi ) + 4.0 * $ e2 * cos ( 4.0 * $ phi ) - 6.0 * $ e3 * cos ( 6.0 * $ phi ) ; $ con1 = 2.0 * $ ml + $ c * ( $ ml * $ ml + $ b ) - 2.0 * $ a * ( $ c * $ ml + 1.0 ) ; $ con2 = $ eccent * $ sin2ph * ( $ ml * $ ml + $ b - 2.0 * $ a * $ ml ) / ( 2.0 * $ c ) ; $ con3 = 2.0 * ( $ a - $ ml ) * ( $ c * $ mlp - 2.0 / $ sin2ph ) - 2.0 * $ mlp ; $ dphi = $ con1 / ( $ con2 + $ con3 ) ; $ phi += $ dphi ; if ( abs ( $ dphi ) <= .0000000001 ) { return ( $ phi ) ; } } Proj4php :: reportError ( 'phi4z: No convergence' ) ; return null ; }
Compute, phi4, the latitude for the inverse of the
Polyconic projection.
Compute phi4 the latitude for the inverse of the Polyconic projection .