ostn02_phf 0.1.3

A PHF map of the OSTN02 grid shifts for use in transforming ETRS89 grid coordinates to OSGB36
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import sys, ctypes
from ctypes import c_uint32, c_double, Structure


class GridRefs(Structure):
    _fields_ = [("eastings", c_uint32),
                ("northings", c_uint32)]

    def __str__(self):
        return "({},{})".format(self.eastings, self.northings)


class Shifts(Structure):
    _fields_ = [("x_shift", c_double),
                ("y_shift", c_double),
                ("z_shift", c_double)]

    def __str__(self):
        return "({}, {}, {})".format(self.x_shift, self.y_shift, self.z_shift)


prefix = "target/release/" + {'win32': ''}.get(sys.platform, 'lib')
extension = {'darwin': '.dylib', 'win32': '.dll'}.get(sys.platform, '.so')
lib = ctypes.cdll.LoadLibrary(prefix + "ostn02_phf" + extension)

lib.get_shifts_ffi.argtypes = (GridRefs,)
lib.get_shifts_ffi.restype = Shifts

tup = GridRefs(651, 313)

print lib.get_shifts_ffi(tup)