navigation.hac: Compute bearing, navigated distance and speed

In echogram: Echogram Visualisation and Analysis

Compute bearing, navigated distance and speed

Description

This function computes navigation course (bearing), navigated distance, time diference and navigation speed between GPS fixes in position data imported from an HAC file.

Usage

navigation.hac(pos)

Arguments

pos	geographic position data from an HAC file, as imported with position.hac.

Details

The bearing and navigated distance are computed with functions bearingRhumb and distVincentyEllipsoid from package geosphere. This function is intended to be called inside read.echogram, rather than being used directly.

Value

A data frame with seven variables:

time.cpu	date and time from the computer CPU during data acquisition.
lon	longitudes.
lat	latitudes.
bearing	navigation course between two consecutive GPS fixes.
navdist	navigated distance between two consecutive GPS fixes.
time.dif	time difference between two consecutive GPS fixes.
navspeed	navigation speed between two consecutive GPS fixes.

Author(s)

Héctor Villalobos

See Also

position.hac, bearingRhumb, distVincentyEllipsoid.

Examples

 hacfile <- system.file("hac", "D20150510-T202221.hac", package="echogram")
 pos <- position.hac( hacfile )
 pos
 pos2 <- navigation.hac(pos)
 pos2

echogram documentation built on April 14, 2025, 1:09 a.m.