
eint - the exponential integral

Calling sequence:
eint(x)

Parameter:

x  --   expression

Overloading:

all

Summary:

The exponential integral is defined as

    eint(x) = int( exp(-t) / t, t=x..infinity )

At the moment, a numerical evaluation is only possible for positive real
arguments. eint(x) is equivalent to igamma(0, x). eint returns the function
call with evaluated arguments, if the argument cannot be evaluated to a
number. eint is a kernel function.

>>  eint(2.4);

      0.2844026093e-1

See also:  igamma

