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Get or set the time of the layers of a SpatRaster. Time can be stored as POSIXlt (date and time, with a resolution of seconds, and a time zone), Date, "months", "years", or "yearmonths".

timeInfo and has.time are helper functions to understand what a time data a SpatRaster has.

Usage

# S4 method for SpatRaster
has.time(x)

# S4 method for SpatRaster
time(x, format="")

# S4 method for SpatRaster
time(x, tstep="")<-value

# S4 method for SpatRaster
timeInfo(x)

See also

Arguments

x

SpatRaster or SpatRasterDataset

format

One of "", "seconds" (POSIXlt), "days" (Date), "yearmonths" (decimal years), "years", "months". If "", the returned format is (based on) the format that was used to set the time

value

Date, POSIXt, yearmon (defined in package zoo), or numeric

tstep

One of "years", "months", "yearmonths". Used when value is numeric. Ignored when value is of type Date, POSIXt, or yearmon

Value

time: POSIXlt, Date, or numeric timeInfo: data.frame with time step and time zone information (if available) has.time: logical

Examples

s <- rast(system.file("ex/logo.tif", package="terra"))   

# Date"
d <- as.Date("2001-05-04") + 0:2
time(s) <- d
time(s)
#> [1] "2001-05-04" "2001-05-05" "2001-05-06"

# POSIX (date/time with a resolution of seconds)
time(s) <- as.POSIXlt(d)
time(s)
#> [1] "2001-05-04 UTC" "2001-05-05 UTC" "2001-05-06 UTC"

# with time zone
time(s) <- as.POSIXlt(Sys.time(), "America/New_York") + 0:2
time(s)
#> [1] "2024-04-23 07:12:17 EDT" "2024-04-23 07:12:18 EDT"
#> [3] "2024-04-23 07:12:19 EDT"
timeInfo(s)
#>   time    step             zone
#> 1 TRUE seconds America/New_York

# years
time(s, tstep="years") <- 2000 + 0:2
s
#> class       : SpatRaster 
#> dimensions  : 77, 101, 3  (nrow, ncol, nlyr)
#> resolution  : 1, 1  (x, y)
#> extent      : 0, 101, 0, 77  (xmin, xmax, ymin, ymax)
#> coord. ref. : Cartesian (Meter) 
#> source      : logo.tif 
#> colors RGB  : 1, 2, 3 
#> names       : red, green, blue 
#> min values  :   0,     0,    0 
#> max values  : 255,   255,  255 
#> time (years): 2000 to 2002 

time(s, tstep="months") <- 1:3
s 
#> class       : SpatRaster 
#> dimensions  : 77, 101, 3  (nrow, ncol, nlyr)
#> resolution  : 1, 1  (x, y)
#> extent      : 0, 101, 0, 77  (xmin, xmax, ymin, ymax)
#> coord. ref. : Cartesian (Meter) 
#> source      : logo.tif 
#> colors RGB  : 1, 2, 3 
#> names       : red, green, blue 
#> min values  :   0,     0,    0 
#> max values  : 255,   255,  255 
#> time (mnts) : Jan to Mar