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# Make changes to this file, not the c-wrappers that Pyrex generates.
include "_pyproj.pxi"
cimport c_numpy
c_numpy.import_array()
def set_datapath(datapath):
cdef char *searchpath
searchpath = PyString_AsString(datapath)
pj_set_searchpath(1, &searchpath)
cdef class Proj:
cdef projPJ projpj
cdef public object proj_version
cdef char *pjinitstring
cdef public object srs
def __new__(self, projstring):
# setup proj initialization string.
self.srs = projstring
self.pjinitstring = PyString_AsString(self.srs)
# initialize projection
self.projpj = pj_init_plus(self.pjinitstring)
if pj_errno != 0:
raise RuntimeError(pj_strerrno(pj_errno))
self.proj_version = PJ_VERSION/100.
def __dealloc__(self):
"""destroy projection definition"""
pj_free(self.projpj)
def __reduce__(self):
"""special method that allows pyproj.Proj instance to be pickled"""
return (self.__class__,(self.srs,))
def _fwd(self, object lons, object lats, radians=False, errcheck=False):
"""
forward transformation - lons,lats to x,y (done in place).
if radians=True, lons/lats are radians instead of degrees.
if errcheck=True, an exception is raised if the forward transformation is invalid.
if errcheck=False and the forward transformation is invalid, no exception is
raised and 1.e30 is returned.
"""
cdef projUV projxyout, projlonlatin
cdef Py_ssize_t buflenx, bufleny, ndim, i
cdef double u, v
cdef double *lonsdata, *latsdata
cdef void *londata, *latdata
# if buffer api is supported, get pointer to data buffers.
if PyObject_AsWriteBuffer(lons, &londata, &buflenx) <> 0:
raise RuntimeError
if PyObject_AsWriteBuffer(lats, &latdata, &bufleny) <> 0:
raise RuntimeError
# process data in buffer
if buflenx != bufleny:
raise RuntimeError("Buffer lengths not the same")
ndim = buflenx/_doublesize
lonsdata = <double *>londata
latsdata = <double *>latdata
for i from 0 <= i < ndim:
if radians:
projlonlatin.u = lonsdata[i]
projlonlatin.v = latsdata[i]
else:
projlonlatin.u = _dg2rad*lonsdata[i]
projlonlatin.v = _dg2rad*latsdata[i]
projxyout = pj_fwd(projlonlatin,self.projpj)
if errcheck and pj_errno != 0:
raise RuntimeError(pj_strerrno(pj_errno))
# since HUGE_VAL can be 'inf',
# change it to a real (but very large) number.
if projxyout.u == HUGE_VAL:
lonsdata[i] = 1.e30
else:
lonsdata[i] = projxyout.u
if projxyout.v == HUGE_VAL:
latsdata[i] = 1.e30
else:
latsdata[i] = projxyout.v
def _inv(self, object x, object y, radians=False, errcheck=False):
"""
inverse transformation - x,y to lons,lats (done in place).
if radians=True, lons/lats are radians instead of degrees.
if errcheck=True, an exception is raised if the inverse transformation is invalid.
if errcheck=False and the inverse transformation is invalid, no exception is
raised and 1.e30 is returned.
"""
cdef projUV projxyin, projlonlatout
cdef Py_ssize_t buflenx, bufleny, ndim, i
cdef double u, v
cdef void *xdata, *ydata
cdef double *xdatab, *ydatab
# if buffer api is supported, get pointer to data buffers.
if PyObject_AsWriteBuffer(x, &xdata, &buflenx) <> 0:
raise RuntimeError
if PyObject_AsWriteBuffer(y, &ydata, &bufleny) <> 0:
raise RuntimeError
# process data in buffer
# (for numpy/regular python arrays).
if buflenx != bufleny:
raise RuntimeError("Buffer lengths not the same")
ndim = buflenx/_doublesize
xdatab = <double *>xdata
ydatab = <double *>ydata
for i from 0 <= i < ndim:
projxyin.u = xdatab[i]
projxyin.v = ydatab[i]
projlonlatout = pj_inv(projxyin,self.projpj)
if errcheck and pj_errno != 0:
raise RuntimeError(pj_strerrno(pj_errno))
# since HUGE_VAL can be 'inf',
# change it to a real (but very large) number.
if projlonlatout.u == HUGE_VAL:
xdatab[i] = 1.e30
elif radians:
xdatab[i] = projlonlatout.u
else:
xdatab[i] = _rad2dg*projlonlatout.u
if projlonlatout.v == HUGE_VAL:
ydatab[i] = 1.e30
elif radians:
ydatab[i] = projlonlatout.v
else:
ydatab[i] = _rad2dg*projlonlatout.v
def _fwdn(self, c_numpy.ndarray lonlat, radians=False, errcheck=False):
"""
forward transformation - lons,lats to x,y (done in place).
Uses ndarray of shape ...,2.
if radians=True, lons/lats are radians instead of degrees.
if errcheck=True, an exception is raised if the forward
transformation is invalid.
if errcheck=False and the forward transformation is
invalid, no exception is
raised and 1.e30 is returned.
"""
cdef projUV projxyout, projlonlatin
cdef projUV *llptr
cdef Py_ssize_t npts, i
npts = c_numpy.PyArray_SIZE(lonlat)//2
llptr = <projUV *>lonlat.data
for i from 0 <= i < npts:
if radians:
projlonlatin = llptr[i]
else:
projlonlatin.u = _dg2rad*llptr[i].u
projlonlatin.v = _dg2rad*llptr[i].v
projxyout = pj_fwd(projlonlatin,self.projpj)
if errcheck and pj_errno != 0:
raise RuntimeError(pj_strerrno(pj_errno))
# since HUGE_VAL can be 'inf',
# change it to a real (but very large) number.
if projxyout.u == HUGE_VAL:
llptr[i].u = 1.e30
else:
llptr[i].u = projxyout.u
if projxyout.v == HUGE_VAL:
llptr[i].u = 1.e30
else:
llptr[i].v = projxyout.v
def _invn(self, c_numpy.ndarray xy, radians=False, errcheck=False):
"""
inverse transformation - x,y to lons,lats (done in place).
Uses ndarray of shape ...,2.
if radians=True, lons/lats are radians instead of degrees.
if errcheck=True, an exception is raised if the inverse transformation is invalid.
if errcheck=False and the inverse transformation is invalid, no exception is
raised and 1.e30 is returned.
"""
cdef projUV projxyin, projlonlatout
cdef projUV *llptr
cdef Py_ssize_t npts, i
npts = c_numpy.PyArray_SIZE(xy)//2
llptr = <projUV *>xy.data
for i from 0 <= i < npts:
projxyin = llptr[i]
projlonlatout = pj_inv(projxyin, self.projpj)
if errcheck and pj_errno != 0:
raise RuntimeError(pj_strerrno(pj_errno))
# since HUGE_VAL can be 'inf',
# change it to a real (but very large) number.
if projlonlatout.u == HUGE_VAL:
llptr[i].u = 1.e30
elif radians:
llptr[i].u = projlonlatout.u
else:
llptr[i].u = _rad2dg*projlonlatout.u
if projlonlatout.v == HUGE_VAL:
llptr[i].v = 1.e30
elif radians:
llptr[i].v = projlonlatout.v
else:
llptr[i].v = _rad2dg*projlonlatout.v
def is_latlong(self):
# returns True if projection in geographic (lon/lat) coordinates
cdef int i
i = pj_is_latlong(self.projpj)
if i:
return True
else:
return False
def is_geocent(self):
# returns True if projection in geocentric (x/y) coordinates
cdef int i
i = pj_is_geocent(self.projpj)
if i:
return True
else:
return False
def _transform(Proj p1, Proj p2, inx, iny, inz, radians):
# private function to call pj_transform
cdef void *xdata, *ydata, *zdata
cdef double *xx, *yy, *zz
cdef Py_ssize_t buflenx, bufleny, buflenz, npts, i
if PyObject_AsWriteBuffer(inx, &xdata, &buflenx) <> 0:
raise RuntimeError
if PyObject_AsWriteBuffer(iny, &ydata, &bufleny) <> 0:
raise RuntimeError
if inz is not None:
if PyObject_AsWriteBuffer(inz, &zdata, &buflenz) <> 0:
raise RuntimeError
else:
buflenz = bufleny
if not (buflenx == bufleny == buflenz):
raise RuntimeError('x,y and z must be same size')
xx = <double *>xdata
yy = <double *>ydata
if inz is not None:
zz = <double *>zdata
npts = buflenx/8
if not radians and p1.is_latlong():
for i from 0 <= i < npts:
xx[i] = xx[i]*_dg2rad
yy[i] = yy[i]*_dg2rad
if inz is not None:
ierr = pj_transform(p1.projpj, p2.projpj, npts, 0, xx, yy, zz)
else:
ierr = pj_transform(p1.projpj, p2.projpj, npts, 0, xx, yy, NULL)
if ierr != 0:
raise RuntimeError(pj_strerrno(ierr))
if not radians and p2.is_latlong():
for i from 0 <= i < npts:
xx[i] = xx[i]*_rad2dg
yy[i] = yy[i]*_rad2dg
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