Chamberlin Trimetric

Classification

Miscellaneous

Available forms

Forward spherical projection

Defined area

Global

Alias

chamb

Domain

2D

Input type

Geodetic coordinates

Output type

Projected coordinates

Chamberlin Trimetric

proj-string: +proj=chamb +lat_1=10 +lon_1=30 +lon_2=40

Parameters

Required

Note

Control points should be oriented clockwise.

+lat_1=<value>

Latitude of the first control point.

+lon_1=<value>

Longitude of the first control point.

+lat_2=<value>

Latitude of the second control point.

+lon_2=<value>

Longitude of the second control point.

+lat_3=<value>

Latitude of the third control point.

+lon_3=<value>

Longitude of the third control point.

Optional

+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=1.5708r

See Projection Units for more information.

+R=<value>

Radius of the sphere, given in meters. If used in conjunction with +ellps, +R takes 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.