I am using the landsat BSL (Bare Soil Line) package from R https://rdrr.io/cran/landsat/man/BSL.html, and I am wondering why the code sample is using llimit 0.005 and not 0.01:
BSL(band3, band4, method = "quantile", ulimit = 0.99, llimit = 0.005)
Source code is at https://rdrr.io/cran/landsat/src/R/BSL.R
I looked at the code and documentation, and documentation says: "The quantile method takes the lowest set of points, those with a NIR/red ratio less than the llimit-th quantile." Is there a reason why llimit parameter is set to 0.005 and not 0.01? Does 0.005 set up a 2 tail region, one at 0.005 and one at 0.99?
I emailed the author of this package but I didn't get a response about this question so I'm hoping someone on GIS SE might know.