Running examples in ‘water-Ex.R’ failed
The error most likely occurred in:

> ### Name: read.WSdata
> ### Title: Prepares weather station data
> ### Aliases: read.WSdata
> 
> ### ** Examples
> 
> csvfile <- system.file("extdata", "apples.csv", package="water")
> MTLfile <- system.file("extdata", "L7.MTL.txt", package="water")
> WS <- read.WSdata(WSdata = csvfile, date.format = "%d/%m/%Y", 
+                   lat=-35.42222, long= -71.38639, elev=201, height= 2.2,
+                   columns=c("date" = 1, "time" = 2, "radiation" = 3,
+                   "wind" = 4, "RH" = 6, "temp" = 7, "rain" = 8), 
+                   MTL = MTLfile)
Warning in read.WSdata(WSdata = csvfile, date.format = "%d/%m/%Y", lat = -35.42222,  :
  As tz = "", assuming the weather station time zone is Pacific/Auckland
Error in Ops.data.frame(WS.after, WS.prev) : 
  ‘-’ only defined for equally-sized data frames
Calls: read.WSdata -> Ops.data.frame
Execution halted

Namespace in Imports field not imported from: ‘lubridate’
  All declared Imports should be used.
Namespace in Imports field not imported from: ‘lubridate’
  All declared Imports should be used.
Namespace in Imports field not imported from: 'lubridate'
  All declared Imports should be used.
Namespace in Imports field not imported from: ‘lubridate’
  All declared Imports should be used.
Namespace in Imports field not imported from: ‘lubridate’
  All declared Imports should be used.
Namespace in Imports field not imported from: ‘lubridate’
  All declared Imports should be used.
Namespace in Imports field not imported from: ‘lubridate’
  All declared Imports should be used.

'LazyData' is specified without a 'data' directory
'LazyData' is specified without a 'data' directory
'LazyData' is specified without a 'data' directory
'LazyData' is specified without a 'data' directory
'LazyData' is specified without a 'data' directory
'LazyData' is specified without a 'data' directory
'LazyData' is specified without a 'data' directory
'LazyData' is specified without a 'data' directory
'LazyData' is specified without a 'data' directory
'LazyData' is specified without a 'data' directory
'LazyData' is specified without a 'data' directory
'LazyData' is specified without a 'data' directory