This package contains a collection of utility functions.

• Functions for printing log messages and formatted output (printf).
• log-sum-exp functions for addition and subtraction on the log-scale.
• Distribution functions for Gumbel, inverse gamma, multivariate normal, and others which are not quite standard.
• A function to generate draws from a given discrete distribution using the Gumbel trick.
• Functions to support maximum likelihood estimation based on optim.
• A Metropolis-Hastings sampler and support functions.
• Commonly used transformations and their inverses such as multinomial logit, polar, and shift-scale.
• A function to compute randomized quantile residuals, which are useful to assess fit in generalized linear models.
• Functions to facilitate common vector operations, constructing a vector of na values and a "not in" operator which indicates whether an element is not in a given set.

The contents of this package are subject to evolve over time.

Several C++ utility functions are provided using the Rcpp API. However, the package purposely does not export R interfaces to these functions. This ensures that the package can be used in environments with a missing or obsolete C++ development environment. C++ functions - both interfaces and implementations - are exported in inst/include. Some examples showing how to use these functions in external code are given in the inst/examples folder.

For more information on exposing C++/Rcpp interfaces from an R package, see the following post on Stack Overflow.