def gfpa(target, illmin, abcorr, obsrvr, relate, refval, adjust, step, nintvals,
         cnfine, result=None):
    """
    Determine time intervals for which a specified constraint
    on the phase angle between an illumination source, a target,
    and observer body centers is met.

    http://naif.jpl.nasa.gov/pub/naif/toolkit_docs/C/cspice/gfpa_c.html

    :param target: Name of the target body.
    :type target: str
    :param illmin: Name of the illuminating body.
    :type illmin: str
    :param abcorr: Aberration correction flag.
    :type abcorr: str
    :param obsrvr: Name of the observing body.
    :type obsrvr: str
    :param relate: Relational operator.
    :type relate: str
    :param refval: Reference value.
    :type refval: float
    :param adjust: Adjustment value for absolute extrema searches.
    :type adjust: float
    :param step: Step size used for locating extrema and roots.
    :type step: float
    :param nintvals: Workspace window interval count.
    :type nintvals: int
    :param cnfine: SPICE window to which the search is restricted.
    :type cnfine: spiceypy.utils.support_types.SpiceCell
    :param result: Optional SPICE window containing results.
    :type result: spiceypy.utils.support_types.SpiceCell
    """
    assert isinstance(cnfine, stypes.SpiceCell)
    assert cnfine.is_double()
    if result is None:
        result = stypes.SPICEDOUBLE_CELL(2000)
    else:
        assert isinstance(result, stypes.SpiceCell)
        assert result.is_double()
    target = stypes.stringToCharP(target)
    illmin = stypes.stringToCharP(illmin)
    abcorr = stypes.stringToCharP(abcorr)
    obsrvr = stypes.stringToCharP(obsrvr)
    relate = stypes.stringToCharP(relate)
    refval = ctypes.c_double(refval)
    adjust = ctypes.c_double(adjust)
    step = ctypes.c_double(step)
    nintvals = ctypes.c_int(nintvals)
    libspice.gfpa_c(target, illmin, abcorr, obsrvr, relate, refval,
                    adjust, step, nintvals, ctypes.byref(cnfine),
                    ctypes.byref(result))
    return result
Determine time intervals for which a specified constraint
    on the phase angle between an illumination source, a target,
    and observer body centers is met.

    http://naif.jpl.nasa.gov/pub/naif/toolkit_docs/C/cspice/gfpa_c.html

    :param target: Name of the target body.
    :type target: str
    :param illmin: Name of the illuminating body.
    :type illmin: str
    :param abcorr: Aberration correction flag.
    :type abcorr: str
    :param obsrvr: Name of the observing body.
    :type obsrvr: str
    :param relate: Relational operator.
    :type relate: str
    :param refval: Reference value.
    :type refval: float
    :param adjust: Adjustment value for absolute extrema searches.
    :type adjust: float
    :param step: Step size used for locating extrema and roots.
    :type step: float
    :param nintvals: Workspace window interval count.
    :type nintvals: int
    :param cnfine: SPICE window to which the search is restricted.
    :type cnfine: spiceypy.utils.support_types.SpiceCell
    :param result: Optional SPICE window containing results.
    :type result: spiceypy.utils.support_types.SpiceCell