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- _geod.Geod(__builtin__.object)
-
- Geod
- _proj.Proj(__builtin__.object)
-
- Proj
class Geod(_geod.Geod) |
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performs forward and inverse geodetic, or Great Circle,
computations. The forward computation (using the 'fwd' method)
involves determining latitude, longitude and back azimuth of a
terminus point given the latitude and longitude of an initial
point, plus azimuth and distance. The inverse computation (using
the 'inv' method) involves determining the forward and back
azimuths and distance given the latitudes and longitudes of an
initial and terminus point.
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- Method resolution order:
- Geod
- _geod.Geod
- __builtin__.object
Methods defined here:
- fwd(self, lons, lats, az, dist, radians=False)
- forward transformation - Returns longitudes, latitudes and back
azimuths of terminus points given longitudes (lons) and
latitudes (lats) of initial points, plus forward azimuths (az)
and distances (dist).
Works with numpy and regular python array objects, python
sequences and scalars.
if radians=True, lons/lats and azimuths are radians instead of
degrees. Distances are in meters.
- inv(self, lons1, lats1, lons2, lats2, radians=False)
- inverse transformation - Returns forward and back azimuths, plus
distances between initial points (specified by lons1, lats1) and
terminus points (specified by lons2, lats2).
Works with numpy and regular python array objects, python
sequences and scalars.
if radians=True, lons/lats and azimuths are radians instead of
degrees. Distances are in meters.
- npts(self, lon1, lat1, lon2, lat2, npts, radians=False)
- Given a single initial point and terminus point (specified by
python floats lon1,lat1 and lon2,lat2), returns a list of
longitude/latitude pairs describing npts equally spaced
intermediate points along the geodesic between the initial and
terminus points.
if radians=True, lons/lats are radians instead of degrees.
Example usage:
>>> from pyproj import Geod
>>> g = Geod(ellps='clrk66') # Use Clarke 1966 ellipsoid.
>>> # specify the lat/lons of Boston and Portland.
>>> boston_lat = 42.+(15./60.); boston_lon = -71.-(7./60.)
>>> portland_lat = 45.+(31./60.); portland_lon = -123.-(41./60.)
>>> # find ten equally spaced points between Boston and Portland.
>>> lonlats = g.npts(boston_lon,boston_lat,portland_lon,portland_lat,10)
>>> for lon,lat in lonlats: print '%6.3f %7.3f' % (lat, lon)
43.528 -75.414
44.637 -79.883
45.565 -84.512
46.299 -89.279
46.830 -94.156
47.149 -99.112
47.251 -104.106
47.136 -109.100
46.805 -114.051
46.262 -118.924
Static methods defined here:
- __new__(self, initparams=None, **kwargs)
- initialize a Geod class instance.
Geodetic parameters for specifying the ellipsoid
can be given in a dictionary 'initparams', as keyword arguments,
or as as proj4 geod initialization string.
Following is a list of the ellipsoids that may be defined using the
'ellps' keyword:
MERIT a=6378137.0 rf=298.257 MERIT 1983
SGS85 a=6378136.0 rf=298.257 Soviet Geodetic System 85
GRS80 a=6378137.0 rf=298.257222101 GRS 1980(IUGG, 1980)
IAU76 a=6378140.0 rf=298.257 IAU 1976
airy a=6377563.396 b=6356256.910 Airy 1830
APL4.9 a=6378137.0. rf=298.25 Appl. Physics. 1965
NWL9D a=6378145.0. rf=298.25 Naval Weapons Lab., 1965
mod_airy a=6377340.189 b=6356034.446 Modified Airy
andrae a=6377104.43 rf=300.0 Andrae 1876 (Den., Iclnd.)
aust_SA a=6378160.0 rf=298.25 Australian Natl & S. Amer. 1969
GRS67 a=6378160.0 rf=298.2471674270 GRS 67(IUGG 1967)
bessel a=6377397.155 rf=299.1528128 Bessel 1841
bess_nam a=6377483.865 rf=299.1528128 Bessel 1841 (Namibia)
clrk66 a=6378206.4 b=6356583.8 Clarke 1866
clrk80 a=6378249.145 rf=293.4663 Clarke 1880 mod.
CPM a=6375738.7 rf=334.29 Comm. des Poids et Mesures 1799
delmbr a=6376428. rf=311.5 Delambre 1810 (Belgium)
engelis a=6378136.05 rf=298.2566 Engelis 1985
evrst30 a=6377276.345 rf=300.8017 Everest 1830
evrst48 a=6377304.063 rf=300.8017 Everest 1948
evrst56 a=6377301.243 rf=300.8017 Everest 1956
evrst69 a=6377295.664 rf=300.8017 Everest 1969
evrstSS a=6377298.556 rf=300.8017 Everest (Sabah & Sarawak)
fschr60 a=6378166. rf=298.3 Fischer (Mercury Datum) 1960
fschr60m a=6378155. rf=298.3 Modified Fischer 1960
fschr68 a=6378150. rf=298.3 Fischer 1968
helmert a=6378200. rf=298.3 Helmert 1906
hough a=6378270.0 rf=297. Hough
intl a=6378388.0 rf=297. International 1909 (Hayford)
krass a=6378245.0 rf=298.3 Krassovsky, 1942
kaula a=6378163. rf=298.24 Kaula 1961
lerch a=6378139. rf=298.257 Lerch 1979
mprts a=6397300. rf=191. Maupertius 1738
new_intl a=6378157.5 b=6356772.2 New International 1967
plessis a=6376523. b=6355863. Plessis 1817 (France)
SEasia a=6378155.0 b=6356773.3205 Southeast Asia
walbeck a=6376896.0 b=6355834.8467 Walbeck
WGS60 a=6378165.0 rf=298.3 WGS 60
WGS66 a=6378145.0 rf=298.25 WGS 66
WGS72 a=6378135.0 rf=298.26 WGS 72
WGS84 a=6378137.0 rf=298.257223563 WGS 84
sphere a=6370997.0 b=6370997.0 Normal Sphere (r=6370997)
The parameters of the ellipsoid may also be set directly using
the 'a' (semi-major or equatorial axis radius) keyword, and
any one of the following keywords: 'b' (semi-minor,
or polar axis radius), 'e' (eccentricity), 'es' (eccentricity
squared), 'f' (flattening), or 'rf' (reciprocal flattening).
See the proj documentation (http://proj.maptools.org) for more
information about specifying ellipsoid parameters (specifically,
the chapter 'Specifying the Earth's figure' in the main Proj
users manual).
Example usage:
>>> from pyproj import Geod
>>> g = Geod(ellps='clrk66') # Use Clarke 1966 ellipsoid.
>>> # specify the lat/lons of some cities.
>>> boston_lat = 42.+(15./60.); boston_lon = -71.-(7./60.)
>>> portland_lat = 45.+(31./60.); portland_lon = -123.-(41./60.)
>>> newyork_lat = 40.+(47./60.); newyork_lon = -73.-(58./60.)
>>> london_lat = 51.+(32./60.); london_lon = -(5./60.)
>>> # compute forward and back azimuths, plus distance
>>> # between Boston and Portland.
>>> az12,az21,dist = g.inv(boston_lon,boston_lat,portland_lon,portland_lat)
>>> print "%7.3f %6.3f %12.3f" % (az12,az21,dist)
-66.531 75.654 4164192.708
>>> # compute latitude, longitude and back azimuth of Portland,
>>> # given Boston lat/lon, forward azimuth and distance to Portland.
>>> endlon, endlat, backaz = g.fwd(boston_lon, boston_lat, az12, dist)
>>> print "%6.3f %6.3f %13.3f" % (endlat,endlon,backaz)
45.517 -123.683 75.654
>>> # compute the azimuths, distances from New York to several
>>> # cities (pass a list)
>>> lons1 = 3*[newyork_lon]; lats1 = 3*[newyork_lat]
>>> lons2 = [boston_lon, portland_lon, london_lon]
>>> lats2 = [boston_lat, portland_lat, london_lat]
>>> az12,az21,dist = g.inv(lons1,lats1,lons2,lats2)
>>> for faz,baz,d in zip(az12,az21,dist): print "%7.3f %7.3f %9.3f" % (faz,baz,d)
54.663 -123.448 288303.720
-65.463 79.342 4013037.318
51.254 -71.576 5579916.649
>>> g2 = Geod('+ellps=clrk66') # use proj4 style initialization string
>>> az12,az21,dist = g2.inv(boston_lon,boston_lat,portland_lon,portland_lat)
>>> print "%7.3f %6.3f %12.3f" % (az12,az21,dist)
-66.531 75.654 4164192.708
Data descriptors defined here:
- __dict__
- dictionary for instance variables (if defined)
- __weakref__
- list of weak references to the object (if defined)
Methods inherited from _geod.Geod:
- __reduce__(...)
- special method that allows pyproj.Geod instance to be pickled
Data descriptors inherited from _geod.Geod:
- geodstring
- proj_version
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class Proj(_proj.Proj) |
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performs cartographic transformations (converts from
longitude,latitude to native map projection x,y coordinates and
vice versa) using proj (http://proj.maptools.org/)
A Proj class instance is initialized with proj map projection
control parameter key/value pairs. The key/value pairs can
either be passed in a dictionary, or as keyword arguments,
or as a proj4 string (compatible with the proj command). See
http://www.remotesensing.org/geotiff/proj_list for examples of
key/value pairs defining different map projections.
Calling a Proj class instance with the arguments lon, lat will
convert lon/lat (in degrees) to x/y native map projection
coordinates (in meters). If optional keyword 'inverse' is True
(default is False), the inverse transformation from x/y to
lon/lat is performed. If optional keyword 'radians' is True
(default is False) lon/lat are interpreted as radians instead of
degrees. If optional keyword 'errcheck' is True (default is
False) an exception is raised if the transformation is invalid.
If errcheck=False and the transformation is invalid, no
exception is raised and 1.e30 is returned. If the optional keyword
'preserve_units' is True, the units in map projection coordinates
are not forced to be meters.
Works with numpy and regular python array objects, python
sequences and scalars.
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- Method resolution order:
- Proj
- _proj.Proj
- __builtin__.object
Methods defined here:
- __call__(self, *args, **kw)
- Calling a Proj class instance with the arguments lon, lat will
convert lon/lat (in degrees) to x/y native map projection
coordinates (in meters). If optional keyword 'inverse' is True
(default is False), the inverse transformation from x/y to
lon/lat is performed. If optional keyword 'radians' is True
(default is False) the units of lon/lat are radians instead of
degrees. If optional keyword 'errcheck' is True (default is
False) an exception is raised if the transformation is invalid.
If errcheck=False and the transformation is invalid, no
exception is raised and 1.e30 is returned.
Instead of calling with lon, lat, a single ndarray of
shape n,2 may be used, and one of the same shape will
be returned; this is more efficient.
Inputs should be doubles (they will be cast to doubles if they
are not, causing a slight performance hit).
Works with numpy and regular python array objects, python
sequences and scalars, but is fastest for array objects.
- is_geocent(self)
- returns True if projection in geocentric (x/y) coordinates
- is_latlong(self)
- returns True if projection in geographic (lon/lat) coordinates
Static methods defined here:
- __new__(self, projparams=None, preserve_units=False, **kwargs)
- initialize a Proj class instance.
Proj4 projection control parameters must either be given in a
dictionary 'projparams' or as keyword arguments. See the proj
documentation (http://proj.maptools.org) for more information
about specifying projection parameters.
Example usage:
>>> from pyproj import Proj
>>> p = Proj(proj='utm',zone=10,ellps='WGS84') # use kwargs
>>> x,y = p(-120.108, 34.36116666)
>>> print 'x=%9.3f y=%11.3f' % (x,y)
x=765975.641 y=3805993.134
>>> print 'lon=%8.3f lat=%5.3f' % p(x,y,inverse=True)
lon=-120.108 lat=34.361
>>> # do 3 cities at a time in a tuple (Fresno, LA, SF)
>>> lons = (-119.72,-118.40,-122.38)
>>> lats = (36.77, 33.93, 37.62 )
>>> x,y = p(lons, lats)
>>> print 'x: %9.3f %9.3f %9.3f' % x
x: 792763.863 925321.537 554714.301
>>> print 'y: %9.3f %9.3f %9.3f' % y
y: 4074377.617 3763936.941 4163835.303
>>> lons, lats = p(x, y, inverse=True) # inverse transform
>>> print 'lons: %8.3f %8.3f %8.3f' % lons
lons: -119.720 -118.400 -122.380
>>> print 'lats: %8.3f %8.3f %8.3f' % lats
lats: 36.770 33.930 37.620
>>> p2 = Proj('+proj=utm +zone=10 +ellps=WGS84') # use proj4 string
>>> x,y = p2(-120.108, 34.36116666)
>>> print 'x=%9.3f y=%11.3f' % (x,y)
x=765975.641 y=3805993.134
>>> p = Proj(init="epsg:32667")
>>> print 'x=%12.3f y=%12.3f (meters)' % p(-114.057222, 51.045)
x=-1783486.760 y= 6193833.196 (meters)
>>> p = Proj("+init=epsg:32667",preserve_units=True)
>>> print 'x=%12.3f y=%12.3f (feet)' % p(-114.057222, 51.045)
x=-5851322.810 y=20320934.409 (feet)
Data descriptors defined here:
- __dict__
- dictionary for instance variables (if defined)
- __weakref__
- list of weak references to the object (if defined)
Methods inherited from _proj.Proj:
- __reduce__(...)
- special method that allows pyproj.Proj instance to be pickled
Data descriptors inherited from _proj.Proj:
- proj_version
- srs
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