Matlab – Calculate angle between 2 geographic coordinates in MATLAB

Using the function trackAzimuth in maptools:

library(maptools)

trackAngle <- function(xy) {
    angles <- abs(c(trackAzimuth(xy), 0) -
                  c(0, rev(trackAzimuth(xy[nrow(xy):1, ]))))
    angles <- ifelse(angles > 180, 360 - angles, angles)
    angles[is.na(angles)] <- 180
    angles[-c(1, length(angles))]
}

The trackAzimuth function is a simple loop wrapper around gzAzimuth. See ?gzAzimuth for references on calculating directions on the sphere.

Using your data:

x <- read.table(text = "longitude                       latitude
36.89379547                0.290166977
36.89384037                0.290194109
36.88999724                0.286821044
36.88708721                0.288339411
36.88650313                0.29010232
36.88563203                0.289939416
36.88545224                0.290924863", header = TRUE)

trackAngle(as.matrix(x))
[1]  10.12946 111.17211 135.88514  97.73801  89.74684

EDIT: I had to remove first/last angles from the function, something I was doing after the fact with this function elsewhere. Should be right now. :)

Also, the packages adehabitatLT and argosfilter contain functions to calculate track directions and angles.

In CoordinateToCoordinate you use sin(coordinate.first) which is already in degrees. Use sin(degreeToRadian(coordinate.first)).

Or to be more cleaner:

... CoordinateToCoordinate (...)
{
  ...
  coordinate.first = asin((sin(latitude) * cos(meters))
                        + (cos(latitude) * sin(meters) * cos(angle)));
  coordinate.second = longitude + atan2((sin(angle) * sin(meters) * cos(latitude)), 
         cos(meters) - (sin(latitude) * sin(coordinate.first)));

  coordinate.first = radianToDegree(coordinate.first);
  coordinate.second = radianToDegree(coordinate.second);

  return coordinate;
}

This fixes the problem. Live Demo.