Exponential Integral

In mathematics, the exponential integral is a special function defined on the complex plane, given by one particular definite integral of the ratio between an exponential function and its argument. It is not an elementary function, a fact that can be demonstrated using the Risch algorithm, and it must instead be evaluated through series expansions or numerical methods. The exponential integral has practical applications in heat transfer, groundwater flow analysis, and radiative transfer calculations. This description is adapted from Wikipedia contributors under CC BY-SA 4.0; changes were made. https://creativecommons.org/licenses/by-sa/4.0/