This R package contains some general utilities that I and maybe others find useful when developing data science software:

calculating density values

catching exceptions

working with Cholesky roots

differencing covariance matrices

working with dates

creating a dictionary

working with functions and their arguments

estimating hidden Markov models

working with indices

working with lists

creating Markov chains

helpers for building an R package

sampling from densities

timed evaluations

user interactions