Accompanying R Package (KernSmooth)
Kernel Smoothing is accompanied by the R package:
Wand, M.P. and Ripley, B.D. (2015).
KernSmooth 2.23. Functions for kernel smoothing corresponding to the book:
Wand, M.P. and Jones, M.C. (1995) "Kernel Smoothing". https://cran.r-project.org
KernSmooth is a base R package in so it does not need to be installed once you have R.
Package web-site on the Comprehensive R Archive Network.