Eckert IV¶
Classification |
Pseudocylindrical |
Available forms |
Forward and inverse, spherical projection |
Defined area |
Global |
Alias |
eck4 |
Domain |
2D |
Input type |
Geodetic coordinates |
Output type |
Projected coordinates |
proj-string: +proj=eck4¶
\[x = \lambda(1+cos\phi) / \sqrt{ 2 + \pi }\]
\[y = 2 \phi / \sqrt { 2 + \pi }\]
Parameters¶
Note
All parameters are optional for the Eckert IV projection.
- +lon_0=<value>¶
Longitude of projection center.
Defaults to 0.0.
Note
The default convention is to interpret this value as decimal degrees. To specify radians instead, follow the value with the "r" character.
Example: +lon_0=1.570796r
See Projection Units for more information.
- +R=<value>¶
Radius of the sphere, given in meters. If used in conjunction with
+ellps,+Rtakes precedence.See Ellipsoid size parameters for more information.
- +x_0=<value>¶
False easting.
Defaults to 0.0.
- +y_0=<value>¶
False northing.
Defaults to 0.0.