geo (version 1.4-3)

invProj: Performs the inverse Mercator or Lambert projection of data.

Description

Accepts data in spherical coordinates with center lattitude 0 and longitude 0 and performs an inverse Mercator, Lambert or no tranformation.

Usage

invProj(x, y = NULL, scale = getOption("geopar")$scale, b0 = getOption("geopar")$b0, b1 = getOption("geopar")$b1, l1 = getOption("geopar")$l1, projection = getOption("geopar")$projection)

Arguments

x,y

The input data to be inversely projected, may be given as two vectors or as list attributes (\$x and \$y).

scale

The scale of the input date (m, km or miles), default is the scale defined in geopar (the scale defined when the plot is initialized).

b0

if projection = Mercator b0 is the center of the Mercator projection. If projection = Lambert b0, b1 are the latitudes defining the Lambert projection. Default are the b0 and b1 defined in geopar.

b1

Second defining latitude for Lambert projection.

l1

The longitude defining the Lambert projection, default is the l1 defined in geopar.

projection

The projection to be inversed, legal projections are "mercator", "Lambert" and "none". Default is the projection defined in geopar.

Value

The function returns a list containing if projection = "none" \$x and \$y, if projection is mercator or Lambert it includes the projection (\$projection), the scale (\$scale), \$lat and \$lon and \$x and \$y.

See Also

invProj, geopar, geoplot.