README.md
In hydroloom: Utilities to Weave Hydrologic Fabrics

hydroloom

Install: remotes::install_github(“doi-usgs/hydroloom”)

hydroloom is a collection of functions to work with hydrologic geospatial fabrics. Hydroloom is designed to provide general hydrologic network functionality for any hydrographic or hydrologic data. The package intended for developers of workflows and other packages that require low level network and network data manipulation utilities.

To Learn More, visit the pkgdown site: https://doi-usgs.github.io/hydroloom/articles/hydroloom.html

Hyroloom has support for attributes that can be seen in:

hydroloom::hydroloom_name_definitions

Click to See Definitions

| Name | Definition | |:--------------------------|:------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------| | id | shared network identifier for catchment divide and flowpath or flowline | | toid | indicates to the downstream id. May or may not be dendritic | | fromnode | indicates the node representing the nexus upstream of a catchment | | tonode | indicates the node representing the nexus downstream of a catchment | | divergence | indicates whether a catchment is not downstream of a diversion (0), the primary path downstream of a divergence (1), or a minor path downstream of a diversion (2). | | wbid | waterbody id | | total_da_sqkm | total drainage area at the outlet of a catchment | | da_sqkm | local drainage area of a catchment | | length_km | length of a single catchment’s flowpath | | pathlength_km | distance from the outlet of a catchment to the terminal outlet of a network | | arbolate_sum | total accumulated length of all upstream flowlines | | topo_sort | Similar to hydrosequence in NHDPlus. Large topo_sort values are upstream of small topo_sort values. Note that there are many valid topological sort orders of a directed graph. | | up_topo_sort | topo sort value of the upstream mainstem | | dn_topo_sort | topo sort value of the downstream mainstem | | dn_minor_topo_sort | topo sort value of the downstream minor network element with the smallest id | | terminal_topo_sort | topo sort value of the outlet network element | | terminal_flag | 1 for network terminous 0 for within network | | terminal_id | id of terminal catchment for entire drainage basin | | start_flag | 1 for a headwater, 0 otherwise | | levelpath | provides an identifier for the collection of flowpaths that make up a single mainstem flowpath of a drainage basin | | up_levelpath | levelpath value of the upstream mainstem | | dn_levelpath | levelpath value of the downstream mainstem | | levelpath_outlet_id | id of outlet catchment of a levelpath | | stream_level | starting at 1 for coastal terminals and 4 for inland terminals increments by 1 for each smaller tributary level | | dn_stream_level | stream level of downstream mainstem network element | | stream_order | starting at 1 for headwaters increments by 1 for each larger tributary level, divergences adopt stream order from upstream but returning divergent network does not increment stream order | | stream_calculator | starting at 1 for headwaters and 0 along diverted paths increments by 1 for each larger tributary level, does no increment along diverted paths. Is equal to stream_order along the dendritic network | | feature_type | descriptive feature type moniker | | feature_type_code | compact feature type identifier | | vector_proc_unit | identifier for processing units based on vector encapsulation | | raster_proc_unit | identifier for processing units based on raster encapsulation | | id_measure | interpolative linear reference measure along a single identified feature | | aggregate_id | aggregate identifier useful for ‘reach’ or ‘flowpath’ aggregation of flowlines | | aggregate_id_measure | interpolative linear reference measure along an aggregate feature | | aggregate_id_from_measure | interpolative linear reference for downstream end of a single feature that makes up an aggregate feature | | aggregate_id_to_measure | interpolative linear reference for the upstream end of a single feature that makes up an aggregate feature | | point_id | identifier of hydrologic location point | | offset | offset distance from point to line in units of linear reference analysis units |

hydroloom supports your attribute names that map to the in-built definitions. See hydroloom_names() for more.

hydroloom supports both dendritic and non-dendritic networks start at this vignette for more.

hydroloom was largely created from components of nhdplusTools:

Blodgett, D., Johnson, J.M., 2022, nhdplusTools: Tools for
  Accessing and Working with the NHDPlus,
  https://doi.org/10.5066/P97AS8JD

hydroloom will support some key functionality of nhdplusTools. Some components of nhdplusTools will be deprecated in a future version of the package in favor of the hydroloom implementation. In general, nhdplusTools will continue to support web service functionality and particulars of the NHDPlus data model. In contrast, hydroloom is intended to be more general and focused specifically on hydro fabric data functionality.

hydroloom implements algorithms documented in:

NHDPlus Attributes:

Moore, R.B., McKay, L.D., Rea, A.H., Bondelid, T.R., Price, C.V., Dewald, T.G., 
  and Johnston, C.M., 2019, User's guide for the national hydrography dataset 
  plus (NHDPlus) high resolution: U.S. Geological Survey Open-File Report 2019–1096, 
  66 p., https://doi.org/10.3133/ofr20191096.

Graph Concepts:

Cormen, T. H., & Leiserson, C. E. (2022). Introduction to 
  Algorithms, fourth edition. MIT Press.

Pfafstetter Attributes:

Verdin, K. L., & Verdin, J. P. (1999). A topological system for 
  delineation and codification of the Earth's river basins. 
  Journal of Hydrology, 218(1–2), 1–12. 
  https://doi.org/10.1016/S0022-1694(99)00011-6

The following definitions have been used as much as possible throughout the package. Terms for rivers: Flowline: A flowline is an linear geometry that represents a segment of a flowing body of water. Some flowlines have no local drainage area and are never aggregate features. Flowpath: A flowpath is a linear geometry that represents the connection between a catchment’s inlet and its outlet. All flowpaths have a local drainage area and may be aggregates of flowlines. Catchment: A physiographic unit with zero or one inlets and one outlet. A catchment is represented by one or more partial realizations; flowpath, divide, and networks of flowpaths and divides. Catchment Divide: The polygon boundary that encompasses a catchment.

Hydroloom uses tibble because dplyr verbs for data.frame was dropping the custom hy attributes.
The data.table package is used for some key joins to enhance scalability but dplyr is preferred for clarity.
hy class tibble standardizes all attribute names in code.
graph representation facilitated by make_index_ids() and make_fromids()
names are plural when referring to identifiers and singular when referring to a numerical attribute.

Disclaimer

This software is preliminary or provisional and is subject to revision. It is being provided to meet the need for timely best science. The software has not received final approval by the U.S. Geological Survey (USGS). No warranty, expressed or implied, is made by the USGS or the U.S. Government as to the functionality of the software and related material nor shall the fact of release constitute any such warranty. The software is provided on the condition that neither the USGS nor the U.S. Government shall be held liable for any damages resulting from the authorized or unauthorized use of the software.