Lib.rs

The exponential integral, often written $\text{Ei}$, equal to the the integral of an exponentiated input over the input itself: $\text{Ei}(t) = \int_{-\infty}^{t} \frac{ e^{u} }{ u } \text{d}u$

All credit goes to GSL's implementation. This repository inherits its GPL license.

lib.rs:

The exponential integral, often written $\text{Ei}$, equal to the the integral of an exponentiated input over the input itself: $\text{Ei}(t) = \int_{-\infty}^{t} \frac{ e^{u} }{ u } \text{d}u$

Inspired by GSL's implementation. Inputs less than 0. Inputs greater than 0.