spDistsN1: Euclidean or Great Circle distance between points
In ramiromagno/fishy:

Description Usage Arguments Details Value Note

View source: R/spDistsN1.R

The function returns a vector of distances between a single 2D point (pts_x, pts_y) and a set of 2D points, provided as two double vectors, pts_x and pts_y.

The distance calculation can be either the Great Circle distance (WGS84 ellipsoid, longlat = TRUE), or the Euclidean distance (longlat = FALSE).

1	spDistsN1(pt_x, pt_y, pts_x, pts_y, longlat = TRUE)

`pt_x`	A `double` scalar, the longitude of the single point.
`pt_y`	A `double` scalar, the latitude of the single point.
`pts_x`	A `double` vector, the longitude of the set of the other points.
`pts_y`	A `double` vector, the latitude of the set of the other points.
`longlat`	A `logical` scalar indicating whether to calculate the Great Circle (WGS84 ellipsoid) distance (`TRUE`) or the Euclidean distance (`FALSE`).

This function is a thin R wrapper around the C function fishy_dists. This function performs no checking on the input, and arguments are passed down to the C implementation as is. This means you should not use this function if you do not know what you are doing.

A double vector of distances in the original metric of the points.

The code is based on the source of sp::spDistsN1. We adapted and included sp::spDistsN1 in this package because of two reasons: (i) to avoid a dependency to sp, as this is the only function used from that package; and (ii) to adapt its prototype to accept vectors instead of matrices, as that fitted better in our workflow.

ramiromagno/fishy documentation built on Feb. 18, 2022, 9 a.m.