is.upstream {HydroCode}

Comparison of Pfafstetter Coded Basins

Description

One point (river segment or subbasin) with Pfafstetter code a on the water system can be queried for beeing upstream or downstream as compared to one or many points b on the water system.

Usage

is.upstream(a, b)

a %up% b

is.downstream(a, b)

a %down% b

Arguments

a

numeric, Pfafstetter coded point

b

numeric, one or more Pfaffstetter coded points

Details

For the scientific background of the Pfafstetter coding system see the literature reference.

The following option(s) can be set via, e.g. options("hydrocode.X" = XX):

hydrocode.parallel:

logical. Defaults to FALSE. The runtime may or may not decrease for very large vectors (length > 50000) on multi-threading processors.

hydrocode.alloddorzero:

logical. Defaults to FALSE. This refers to the original Pfafstetter coding system and tests, whether all n numbers are odd, [13579]{n}. Hydrocodes that contain the digit 0 are interpreted as closed catchments (endorheic basins). This setting works, e.g. with the Pfafstetter coded table riversegments of CCM River and Catchment Database, v2.1 (European Commission - JRC, 2007; Vogt et al., 2007). For decoding the Pfafstetter coded tables of the HydroBASIN, v1c dataset (Lehner and Grill, 2013), this option should be set to options("hydrocode.alloddorzero" = TRUE). This tests for all n numbers are odd or zero, [013579]{n}.

Value

a vector of type logical

References

A. L. de Jager and J. V. Vogt, 2010, Development and Demonstration of a Structured Hydrological Feature Coding System for Europe, Hydrological Sciences Journal, 55, 661–75, doi:10.1080/02626667.2010.490786.

B. Lehner and G. Grill, 2013, Global river hydrography and network routing: baseline data and new approaches to study the world’s large river systems, Hydrological Processes, 27, 2171–2186, doi:10.1002/hyp.9740.

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

J. Vogt, P. Soille, A. de Jager, E. Rimavičiūtė, W. Mehl, S. Foisneau, K. Bódis, et al., 2007, A Pan-European River and Catchment Database, Publications Office: Luxembourg, doi:10.2788/35907.

Wikipedia contributors, 2019, Pfafstetter Coding System, In Wikipedia, The Free Encyclopedia, Retrieved 13:23, November 9, 2019, https://en.wikipedia.org/w/index.php?title=Pfafstetter_Coding_System&oldid=907987995

See Also

options

Examples

## example from Wikipedia
## 8835 is upstream of segments 8833 and 8811,
## but not segments 8832, 8821 or 9135
dwn <- c(8833, 8811, 8832, 8821, 9135)
is.upstream(8835, dwn)

## works with operator
8835 %up% dwn

## this will produce errors
## Not run: 
is.upstream("12h", 123)
is.upstream(12.4, 123)

## End(Not run)

## example from Verdin and Verdin, 1999, p. 10
b <- c(8883, 8881, 8879, 8877, 8875, 8873, 8871, 8859,
       8857, 8855, 8853, 8851, 8839, 8837, 8835, 8833,
       8831, 8819, 8817, 8815, 8813, 8811, 8886, 8887,
       8888, 8889)
a <- 8885
a %down% b

## example from Vogt et al. (2007),
## pollution source at 464.
## Which subcatchments are
## affected? Mixed levels of subdivisions.
a <- 464
b <- c(465, 466, 467, 47, 48, 49,
       463, 461, 41, 43, 45, 452,
       454)
a %up% b

## same hydro codes return TRUE per default
112 %up% 112
112 %down% 112