pnp: Check if a point is within a polygon (2D)
In recexcavAAR: 3D Reconstruction of Archaeological Excavations

Description Usage Arguments Details Value See Also Examples

pnp is able to determine if a point is within a polygon in 2D space. The polygon is described by its corner points. The points must be in a correct drawing order.

1	pnp(vertx, verty, testx, testy)

`vertx`	vector of x axis values of polygon corner points
`verty`	vector of y axis values of polygon corner points
`testx`	x axis value of point of interest
`testy`	y axis value of point of interest

For discussion see: http://stackoverflow.com/questions/217578/how-can-i-determine-whether-a-2d-point-is-within-a-polygon/2922778#2922778

boolean value - TRUE, if the point is within the polygon. Otherwise FALSE.

Other pnpfuncs: pnpmulti

df <- data.frame(
  x = c(1,1,2,2),
  y = c(1,2,1,2)
)

pnp(df$x, df$y, 1.5, 1.5)
pnp(df$x, df$y, 2.5, 2.5)

# caution: false-negatives in edge-cases:
pnp(df$x, df$y, 2, 1.5)