R: Compute Euclidean distance along a gradient.

dist.along.grad {sharpshootR}

R Documentation

Compute Euclidean distance along a gradient.

This function computes Euclidean distance along points aligned to a given gradient (e.g. elevation).

dist.along.grad(coords, var, grad.scaled.min, grad.scaled.max)

`coords`	a matrix of x and y coordinates in some projected coordinate system
`var`	a vector of the same length as `coords`, describing the gradient of interest
`grad.scaled.min`	min value of rescaled gradient values
`grad.scaled.max`	max value of rescaled gradient values

This function is primarily intended for use within plotTransect.

A data.frame object:

scaled.grad: scaled gradient values
scaled.distance: cumulative distance, scaled to the interval of 0.5, nrow(coords) + 0.5
distance: cumulative distance computed along gradient, e.g. transect distance
variable: sorted gradient values
x: x coordinates, ordered by gradient values
y: y coordinate, ordered by gradient values
grad.order: a vector index describing the sort order defined by gradient values

This function is very much a work in progress, ideas welcome.

D.E. Beaudette