ind2path: Create a 'path' from indices of coordinates

In Rafnuss/GeoPressureR: Global Positioning by Atmospheric Pressure

Create a path from indices of coordinates

Description

Convert a vector of 2D coordinate indices into a path data.frame. If ind is a matrix, each row represents the path of a different trajectory j.

This function is the main way to create path in GeoPressureR, and is used by graph_most_likely, graph_simulation and tag2path.

Usage

ind2path(ind, tag_graph, use_known = TRUE)

Arguments

ind	vector of indices of the 2D map (vector or matrix)
tag_graph	either a tag or a graph object, must contains stap, extent and scale.
use_known	If true, enforce the known position in the path created. The known positions are approximated to the map resolution in order to corresponds to integer index.

Value

A path data.frame

• stap_id stationary period identification

• j identification for each trajectory (1 to nj).

• lat Latitude,

• lon longitude

• ... other columns from stap

See Also

Other path: path2edge(), path2elevation(), plot_path()

Examples

withr::with_dir(system.file("extdata", package = "GeoPressureR"), {
  tag <- tag_create("18LX", quiet = TRUE) |>
    tag_label(quiet = TRUE) |>
    tag_set_map(c(-16, 23, 0, 50), scale = 1)
})

# ind generated by `graph_most_likely` (single trajectory - vector)
ind <- c(1652, 1603, 1755, 1708, 1607)
path <- ind2path(ind, tag)
knitr::kable(path)

# ind generated by `graph_simulation` (10 trajectories - matrix)
ind <- matrix(c(
  1652, 1652, 1652, 1652, 1652, 1652, 1652, 1652, 1652, 1652,
  1653, 1606, 1653, 1504, 1604, 1704, 1504, 1653, 1753, 1701,
  1805, 1457, 1408, 1657, 1609, 1903, 1506, 1757, 1856, 1804,
  1607, 1514, 1611, 1457, 1860, 1802, 1759, 1609, 1760, 1208,
  1505, 1314, 1559, 1357, 1758, 1852, 1661, 1706, 1862, 1358
), nrow = 10)
path <- ind2path(ind, tag)
knitr::kable(head(path, n = 15))

Rafnuss/GeoPressureR documentation built on April 17, 2025, 12:58 p.m.