spycial.e1

spycial.e1 = <numba._DUFunc 'e1'>

Exponential integral \(E_1(x)\).

For real \(x > 0\) the exponential integral can be defined as [1]

\[E_1(x) = \int_x^\infty \frac{e^{-t}}{t} dt.\]

Parameters:

• x (array-like) – Points on the real line
• out (ndarray, optional) – Output array for the values of e1 at x

Returns:

Values of e1 at x

Return type:

ndarray

See also

ei

Exponential integral \(Ei\)

en

Generalization of \(E_1\)

References

[1]	Digital Library of Mathematical Functions, 6.2.1 https://dlmf.nist.gov/6.2#E1