match_sensors: Match spectra at sensor transitions
In spectrolab: Class and Methods for Spectral Data

match_sensors

R Documentation

Match spectra at sensor transitions

Description

match_sensors scales values of sensors 1 (VIS) and 3 (SWIR 2)

Usage

match_sensors(x, splice_at, fixed_sensor = 2, interpolate_wvl = c(5, 1))

## S3 method for class 'spectra'
match_sensors(x, splice_at, fixed_sensor = 2, interpolate_wvl = c(5, 2))

Arguments

`x`	spectra object
`splice_at`	bands that serve as splice points, i.e the beginnings of the rightmost sensor. Must be length 1 or 2 (max 3 sensors)
`fixed_sensor`	sensor to keep fixed. Can be 1 or 2 if matching 2 sensors. If matching 3 sensors, 'fixed_sensor' must be 2 (default).
`interpolate_wvl`	extent around splice_at values over which the splicing factors will be calculated. Defaults to 5

Details

Splice_at has no default because sensor transition points vary between vendors and individual instruments. The function guess_splice_at can help you guess what those values could be. However, splice_at is an important parameter though, so you should visually inspect your spectra before assigning it. Typical values in our own individual instruments were: SVC ~ c(990, 1900), ASD ~ c(1001, 1801).

If the factors used to match spectra are unreasonable, match_sensors will throw. Unreasonable factors (f) are defined as 0.5 > f > 3 or NaN, which happens when the value for the right sensor is 0.