spacetime: STSDF-class – R documentation

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STSDF-class

Class "STSDF"

Description

A class for spatio-temporal data with partial space-time grids; for n spatial locations and m times, an index table is kept for which nodes observations are available

Usage

STS(sp, time, index, endTime = delta(time))
  STSDF(sp, time, data, index, endTime = delta(time))
  ## S4 method for signature 'STSDF'
x[i, j, ..., drop = is(x, "STSDF")]
  ## S4 method for signature 'STSDF,STFDF'
coerce(from, to, strict=TRUE)
  ## S4 method for signature 'STSDF,STIDF'
coerce(from, to, strict=TRUE)

Arguments

`sp`	object of class Spatial
`time`	object holding time information; see ST-class
`data`	data frame with rows corresponding to the observations (spatial index moving faster than temporal)
`index`	two-column matrix: rows corresponding to the nodes for which observations are available, first column giving spatial index, second column giving temporal index
`endTime`	vector of class `POSIXct` with end points of time intervals for the observations
`x`	an object of class STFDF
`i`	selection of spatial entities
`j`	selection of temporal entities (see syntax in package xts)
`...`	selection of attribute(s)
`drop`	if TRUE and a single spatial entity is selected, an object of class xts is returned; if TRUE and a single temporal entity is selected, and object of the appropriate `Spatial` class is returned; if FALSE, no coercion to reduced classes takes place
`from`	object of class STFDF
`to`	target class
`strict`	ignored

Objects from the Class

Objects of this class carry sparse space/time grid data

Slots

sp:: Object of class "Spatial"
time:: Object holding time information; see ST-class for permitted types
index:: matrix of dimension n x 2, where n matches the number of rows in slot data
data:: Object of class data.frame, which holds the measured values

Methods

[: signature(x = "STSDF"): selects spatial entities, temporal entities, and attributes
plot: signature(x = "STS", y = "missing"): plots space-time layout
plot: signature(x = "STSDF", y = "missing"): plots space-time layout, indicating records partially NA

Author(s)

Edzer Pebesma, edzer.pebesma@uni-muenster.de

References

https://www.jstatsoft.org/v51/i07/

Examples

sp = cbind(x = c(0,0,1), y = c(0,1,1))
row.names(sp) = paste("point", 1:nrow(sp), sep="")
library(sp)
sp = SpatialPoints(sp)
library(xts)
time = xts(1:4, as.POSIXct("2010-08-05")+3600*(10:13))
m = c(10,20,30) # means for each of the 3 point locations
mydata = rnorm(length(sp)*length(time),mean=rep(m, 4))
IDs = paste("ID",1:length(mydata))
mydata = data.frame(values = signif(mydata,3), ID=IDs)
stfdf = STFDF(sp, time, mydata)
stfdf
stsdf = as(stfdf, "STSDF")
stsdf[1:2,]
stsdf[,1:2]
stsdf[,,2]
stsdf[,,"values"]
stsdf[1,]
stsdf[,2]
# examples for [[, [[<-, $ and $<- 
stsdf[[1]]
stsdf[["values"]]
stsdf[["newVal"]] <- rnorm(12)
stsdf$ID
stsdf$ID = paste("OldIDs", 1:12, sep="")
stsdf$NewID = paste("NewIDs", 12:1, sep="")
stsdf
x = stsdf[stsdf,]
x = stsdf[stsdf[1:2,],]
all.equal(x, stsdf[1:2,])

spacetime

Classes and Methods for Spatio-Temporal Data

v1.2-4

GPL (>= 2)

Authors

Edzer Pebesma [aut, cre] (<https://orcid.org/0000-0001-8049-7069>), Benedikt Graeler [ctb], Tom Gottfried [ctb], Robert J. Hijmans [ctb]

Initial release