Cylindrical projection of a window centered
        at (lat0, long0) with a given radius (km).

        Args:
            radius(float): Radius of the window (km).
            lat0(float): Latitude at the center (degree).
            long0(float): Longitude at the center (degree).

        Returns:
            A tuple ``(longll, longtr, latll, lattr)`` with ``longll``
            the longitude of the lower left corner, ``longtr`` the
            longitude of the top right corner, ``latll`` the latitude
            of the lower left corner and ``lattr`` the latitude of the
            top right corner.

        Note:
            All return coordinates are in degree

def cylindrical_window(self, radius, lat0, long0):
        ''' Cylindrical projection of a window centered
        at (lat0, long0) with a given radius (km).

        Args:
            radius(float): Radius of the window (km).
            lat0(float): Latitude at the center (degree).
            long0(float): Longitude at the center (degree).

        Returns:
            A tuple ``(longll, longtr, latll, lattr)`` with ``longll``
            the longitude of the lower left corner, ``longtr`` the
            longitude of the top right corner, ``latll`` the latitude
            of the lower left corner and ``lattr`` the latitude of the
            top right corner.

        Note:
            All return coordinates are in degree        
        '''

        # Passage en radian
        radi = radius * 2 * np.pi / (2 * 1734.4 * np.pi)
        lamb0 = long0 * np.pi / 180.0
        phi0 = lat0 * np.pi / 180.0

        # Long/lat min (voir wikipedia)
        longll = -radi / np.cos(phi0) + lamb0
        latll = np.arcsin((-radi + np.sin(phi0) / np.cos(phi0)) * np.cos(phi0))
        if np.isnan(latll):
            latll = -90 * np.pi / 180.0
        # Long/lat max (voir wikipedia)
        longtr = radi / np.cos(phi0) + lamb0
        lattr = np.arcsin((radi + np.tan(phi0)) * np.cos(phi0))

        return longll * 180 / np.pi, longtr * 180 / np.pi, latll * 180 / np.pi, lattr * 180 / np.pi