JensenTrapezoid {wflo}

Computes the four corner points of a Jensen trapezoid (or cone).

Description

Provided a wind direction, a point and a downwind length, computes the corner points of a Jensen trapezoid (in the literature oftentimes called a 'cone').

Usage

JensenTrapezoid(WindDir, Point, x, Margin = TRUE)

Arguments

WindDir

unique value, a wind direction in degrees.

Point

a vector of two containing x and y coordinates of a point. Usually, both will be between 0 and 1.

x

downwind distance of the cone in meters.

Margin

specified whether to add a small margin to the distance parameter (i.e. internally, compute x * 1.1). Defaults to TRUE.

Value

JensenTrapezoid returns a matrix of four columns (the four corner points) and two rows (x and y coordinates).

Author(s)

Carsten Croonenbroeck

References

Jensen, N. O. (1983). A note on wind generator interaction. Roskilde: Riso National Laboratory. Riso-M, No. 2411

See Also

JensenAngle to compute 'cone' angle information, PointInPolygon for a test whether a point is inside a polygon.

Examples

MyTrapezoid <- JensenTrapezoid(45, c(0.5, 0.5), 500)