water (version 0.5)

read.WSdata: Prepares weather station data

Description

Prepares weather station data

Usage

read.WSdata(WSdata, ..., height = 2.2, lat, long, elev, columns = c("date", "time", "radiation", "wind", NA, "RH", "temp", "pp"), date.format = "%Y-%m-%d", time.format = "%H:%M:%S", datetime.format = "%Y-%m-%d %H:%M:%S", tz = "", cf = c(1, 1, 1), MTL)

Arguments

WSdata

csv file with weather station data

...

additional parameter to pass to read.csv()

height

weather station sensors height in meters

lat

latitude of weather station in decimal degrees. Negative values for south latitude

long

longitude of weather station in decimal degrees. Negative values for west longitude

elev

elevation of weather station in meters

columns

columns order of needed data. Vector containing "date", "time", "radiation", "wind", "RH" and "temp". Other values are ignored. If you have a column with date and time in the same column, you can include "datetime" and "date" and "time" are no longer needed.

date.format

date format. See strptime format argument.

time.format

time format. See strptime format argument.

datetime.format

datetime format. See strptime format argument.

tz

timezone of the weather station dates. If not present assumes the same timezone as the computer running the code. See strptime for details.

cf

conversion factor to convert radiation, wind, and temperature to W/m2; m/s and Celsius. See Details.

MTL

Metadata file. If not provided will look for one on working directory. If provided or present will calculate weather conditions on satellite overpass.

Value

waterWeatherStation object, with data.frames with all data, hourly data and conditions at satellite flyby.

Details

For cf, if your data is in W/m2, km/h and Celsius (radiation, wind, temperature), cf should be: cf = c(1,0.2777778,1)

References

Landsat 7 Metadata example file available from the U.S. Geological Survey. Weather Station example file courtesy of CITRA, Universidad de Talca, Chile

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,
                  MTL = MTLfile)
print(WS)
plot(WS, alldata=FALSE)
plot(WS, alldata=TRUE)