get_UM: Navigate Upstream Mainstem

In nhdplusTools: NHDPlus Tools

Navigate Upstream Mainstem

Description

Traverse NHDPlus network upstream main stem

Usage

get_UM(network, comid, distance = NULL, sort = FALSE, include = TRUE)

Arguments

network	data.frame NHDPlus flowlines including at a minimum: COMID,Pathlength, LevelPathI, and Hydroseq.
comid	integer identifier to start navigating from.
distance	numeric distance in km to limit how many COMIDs are
sort	if TRUE, the returned COMID vector will be sorted in order of distance from the input COMID (nearest to farthest)
include	if TRUE, the input COMID will be included in the returned COMID vector returned. The COMID that exceeds the distance specified is returned.

Value

integer vector of all COMIDs upstream of the starting COMID along the mainstem

nhdplusTools documentation built on Sept. 2, 2026, 9:07 a.m.