public function patchN(int $n) : Polygon
    {
        if (! isset($this->patches[$n - 1])) {
            throw new NoSuchGeometryException('There is no patch in this PolyhedralSurface at index ' . $n);
        }

        return $this->patches[$n - 1];
    }
public function patchN(int $n) : Polygon
    {
        if (! isset($this->patches[$n - 1])) {
            throw new NoSuchGeometryException('There is no patch in this PolyhedralSurface at index ' . $n);
        }

        return $this->patches[$n - 1];
    }
public function patchN ( int $ n ) : Polygon { if ( ! isset ( $ this -> patches [ $ n - 1 ] ) ) { throw new NoSuchGeometryException ( 'There is no patch in this PolyhedralSurface at index ' . $ n ) ; } return $ this -> patches [ $ n - 1 ] ; }
Returns the specified patch N in this PolyhedralSurface.

@param int $n The patch number, 1-based.

@return Polygon

@throws NoSuchGeometryException If there is no patch at this index.
Returns the specified patch N in this PolyhedralSurface .