# [R-pkgs] Announcing new package expint

Vincent Goulet vincent.goulet at me.com
Thu Jan 12 02:55:28 CET 2017

I am pleased to announce the immediate availability on CRAN of the new
package expint: https://cran.r-project.org/package=expint.

The exponential integral

E_1(x) = int_x^\Inf exp(-t)/t dt,  x real

and the incomplete gamma function

G(a, x) = \int_x^\Inf t^{a-1} exp(-t) dt, x > 0, a real

are two closely related functions that arise in various fields of
mathematics.

expint is a small package that intends to fill a gap in R's
support for mathematical functions by providing facilities to compute
the exponential integral and the incomplete gamma function.

Furthermore, and perhaps most conveniently for R package developers,