sl.uvw2uv: Coordinate transformation of velocity vectors (3D -> 2D)

In FESOM/spheRlab: Spherical Geometry, Analysis, and Plotting of Geoscientific Data on Arbitrary Grids

Coordinate transformation of velocity vectors (3D -> 2D)

Description

Convert velocities from u-v-w coordinates (3D) on the unit sphere to u-v-components in local coordinate system (2D).

Usage

sl.uv2uvw(u, v, w, lon, lat, do.d2r = TRUE)

Arguments

u, v, w	numerical vectors (or scalars) for the velocity components.
lon, lat	numerical vectors (or scalars) of longitudes (lon) and latitudes (lat) of the velocity vectors.
do.d2r	a logical scalar (default: TRUE), specifying whether longitude and latitude are interpreted as radian (FALSE) or degrees (TRUE).

Value

Returns a list containing

u	first converted velocity component in local coordinate system
v	second converted velocity component in local coordinate system

Note

The inverse transformation is implemented in sl.uv2uvw.

Author(s)

Simon Reifenberg

See Also

sl.uv2uvw

Examples

# define local velocity vectors at three positions
lon = c(0, 45, 90)
lat = c(0, 45,  0)
u   = c(0, sqrt(2)/2, 1)
v   = c(1, sqrt(2)/2, 0)

# convert to 'global' coordinates
U <- sl.uv2uvw(u, v, lon, lat)
print(U)


# convert back to local coordinates
U.loc <- sl.uvw2uv(U$u, U$v, U$w, lon, lat, do.d2r = T)
print(U.loc)

FESOM/spheRlab documentation built on April 6, 2024, 6:52 p.m.