birdring (version 1.3)

mercatorlat: gives the streching factor of the latitude to draw a mercator map

Description

this function is only used internally by the function draw.map

Usage

mercatorlat(x)

Arguments

x

latitude in decimal coordinates

Value

numeric: latitude to draw a mercator map

References

Rummler, H. (2002) Mercatorkarte und hyperbolische Geometrie. Elem. Math., 57, 168-173.

Examples

# NOT RUN {
mercatorlat(41.6)
# }