run_swath2grid_mod02nrt: Run MRTSwath swath2grid tool

In proccalibrad: Extraction of Bands from MODIS Calibrated Radiances MOD02 NRT

Description

MRTSwath is the "MODIS Reprojection Tool for swath products". See: https://lpdaac.usgs.gov/tools/modis_reprojection_tool_swath).

Usage

run_swath2grid_mod02nrt(mrtpath = "swath2grid", prmfn = "tmpMRTparams.prm",
  tifsdir, modfn, geoloc_fn, ul_lon, ul_lat, lr_lon, lr_lat)

Arguments

mrtpath	This is the path to the MRTSwath executable swath2grid. If your ~/.Rprofile file has the location of swath2grid in the PATH, then you can just use mrtpath="swath2grid". Otherwise, the user must provide the full path to swath2grid.
prmfn	The name of the parameter/control file which will be the input to MRTSwath's swath2grid function.
tifsdir	The directory to save the output TIF files in
modfn	The filename of the MODIS data
geoloc_fn	The filename of the corresponding geolocation file (annoyingly, this is a much larger file than the data file!)
ul_lon	Upper left (ul) longitude (x-coordinate) for subsetting
ul_lat	Upper left (ul) latitude (y-coordinate) for subsetting
lr_lon	Lower right (lr) longitude (x-coordinate) for subsetting
lr_lat	Lower right (lr) latitude (y-coordinate) for subsetting

Details

If you want this function to use MRTSwath tool successfully, you should add the directory with the MRTSwath executable to the default R PATH by editing ~/.Rprofile.

Value

cmdstr The string giving the system command that ran swath2grid

See Also

write_MRTSwath_param_file_mod02nrt

http://landweb.nascom.nasa.gov/cgi-bin/QA_WWW/newPage.cgi?fileName=hdf_filename @cite NASA2001

Examples

#######################################################
# Run MRTSwath tool "swath2grid"
#######################################################

# Source MODIS files (both data and geolocation)
# Code excluded from CRAN check because it depends on modiscdata
## Not run: 
library(devtools)
library(modiscdata)
moddir = system.file("extdata/2002raw/", package="modiscdata")

# Get the matching data/geolocation file pairs
fns_df = check_for_matching_geolocation_files(moddir, modtxt="MOD02", geoloctxt="MOD03")
fns_df

# Resulting TIF files go in this directory
tifsdir = getwd()


# Box to subset
ul_lat = 13
ul_lon = -87
lr_lat = 8
lr_lon = -82

for (i in 1:nrow(fns_df))
	{

prmfn = write_MRTSwath_param_file_mod02nrt(prmfn="tmpMRTparams.prm", tifsdir=tifsdir,
 modfn=fns_df$mod02_fns[i], geoloc_fn=fns_df$mod03_fns[i], ul_lon=ul_lon, ul_lat=ul_lat,
  lr_lon=lr_lon, lr_lat=lr_lat)
print(scan(file=prmfn, what="character", sep="\n"))

run_swath2grid_mod02nrt(mrtpath="swath2grid", prmfn="tmpMRTparams.prm", tifsdir=tifsdir,
 modfn=fns_df$mod302_fns[i], geoloc_fn=fns_df$mod03_fns[i], ul_lon=ul_lon, ul_lat=ul_lat,
  lr_lon=lr_lon, lr_lat=lr_lat)

	}

list.files(tifsdir, pattern=".tif", full.names=TRUE)

## End(Not run)

proccalibrad documentation built on May 2, 2019, 3:18 p.m.