MODIStsp_process_indexes: MODIStsp helper for computing spectral indexes
In lbusett/MODIStsp: Find, Download and Process MODIS Land Products Data

View source: R/MODIStsp_process_indexes.R

MODIStsp_process_indexes

R Documentation

MODIStsp helper for computing spectral indexes

Description

function used to compute spectral indexes, given the index formula

Usage

MODIStsp_process_indexes(
  out_filename,
  out_prod_folder,
  formula,
  bandnames,
  nodata_out,
  indexes_nodata_out,
  file_prefix,
  compress,
  yy,
  out_format,
  DOY,
  scale_val
)

Arguments

`out_filename`	`character` basename of the file in to which save results
`out_prod_folder`	`character` output folder for the product used to retrieve filenames of rasters of original bands to be used in computations
`formula`	`character` Index formula, as derived from XML file and stored in prod_opts within previous_file
`bandnames`	`character` array of names of original HDF layer. Used to identify the bands required for index computation
`nodata_out`	`character` array of NoData values of reflectance bands
`indexes_nodata_out`	`character` NoData value for resulting raster
`file_prefix`	`character` used to retrieve filenames of rasters of original bands to be used in computations
`compress`	`character` compression option for GTiff files
`yy`	`character` year string used to retrieve filenames of rasters of original bands to be used in computations
`out_format`	`character` string used to retrieve filenames of rasters of original bands to be used in computations
`DOY`	`character` doy string used to retrieve filenames of rasters of original bands to be used in computations
`scale_val`	`character` (Yes/No) if Yes, output values in are computed as float -1 - 1, otherwise integer -10000 - 10000

Details

the function parses the index formula to identify the required bands. On the basis of identified bands, it retrieves the reflectance bands required, gets the data into R raster objects, performs the computation and stores results in a GeoTiff or ENVI raster file