krigeLUD: Apply kriging of drainage area ratio

In wfarmer-usgs/PUBAD: Appliles and Analyzes Several Methods for Prediction in Ungaged Basins

Description

The function krigeLUD uses daily variograms of the logarithm of the unit discharge to predict streamflows at the target locations.

Usage

krigeLUD(index.gages, index.baschar, index.obs, target.gages, target.baschar,
  target.obs, zero.val = NA, FixNug = F, FixKap = T, numbins = 10,
  distperc = 1, CovMod = "spherical", pooled = FALSE, neighs = NA)

Arguments

index.gages	A numeric vector of the streamgage IDs to be used as potential index sites.
index.baschar	A data frame with the LAT_GAGE_UTM, LNG_GAGE_UTM and DRAIN_SQKM for each item of index.gages.
index.obs	A zoo object of the observed streamflows for each index gage.
target.gages	A numeric vector of the streamgage IDs to be used as target sites.
target.baschar	Identical to index.baschar with respect to target.gages.
target.obs	A zoo object of the observed streamflows for each target gage.
zero.val	(optional) A value to replace zeros. The deafult is NA.
FixNug	(optional) A logical value indicating if the nugget value should be fixed. The deafult is FALSE.
FixKap	(optional) A logical value indicating if the kappa value should be fixed. The deafult is TRUE.
numbins	(optional) The number of bins to be used in each variogram. The deafult is 10.
distperc	(optional) The percentile of the distances that should constrain the range of the empirical variograms. The defaul is 1.
CovMod	(optional) A character string indicating which theoretical variogram model should be used. The deafult is the 'spherical' model.
pooled	(optional) A logical indicating if the parameters should be computed for every day or on a pooled variogram. The default (FALSE) calls for daily parameters.
neighs	(optional) An integer value specifying how many neighbors to consider. The default (NA) uses all relevant neighbors.

Details

Lorem ipsum...

Value

A list of two elements:

OKLUD

A list with each element corresponding to target.gages, with each element of that list containg a data frame of dateThe date of the row. estThe estimated streamflow values for each day. est.LUDThe raw kriged logarithm of the unit discharge for each day. est.LUD.varThe variance of the raw kriged logarithm of the unit discharge for each day. extrapA logical indicating if the estimate was extrapolated using nearest-neighbor drainage area ratios. ratioIf extrapolation was used, the ratio between target and index locations. indexflowIf extrapolation was used, the index streamflow. indexIf extrapolation was used, the index ID. metricIf extrapolation was used, the similarity metric between the index and target. obsThe observed streamflow.

varPar

A data frame of daily variogram parameters. These include covariance parameters, nugget values, kappa values, the variogram value, the covariance model, the maximum distance, the distance percentile and the number of bins.

wfarmer-usgs/PUBAD documentation built on May 4, 2019, 5:21 a.m.