TOMS385
Exponential Integral Ei(x)

TOMS385 is a FORTRAN77 library which implements ACM TOMS algorithm 385, for evaluating the exponential integral Ei(x).

The text of many ACM TOMS algorithms is available online through ACM: http://www.acm.org/pubs/calgo or NETLIB: http://www.netlib.org/toms/index.html.

Languages:

TOMS385 is available in a FORTRAN77 version.

Related Data and Programs:

TEST_VALUES, a FORTRAN77 library which supplies test values of various mathematical functions.

Reference:

1. Kathleen Paciorek,
   Algorithm 385: Exponential Integral Ei(x),
   Communications of the ACM,
   Volume 13, Number 7, July 1970, pages 446-447.

Source Code:

• toms385.f, the source code.
• toms385.sh, commands to compile the source code.

Examples and Tests:

• toms385_prb.f, a sample calling program.
• toms385_prb.sh, commands to compile and run the sample program.
• toms385_prb_output.txt, the output file.

List of Routines:

• DEI evaluates the exponential integral.

You can go up one level to the FORTRAN77 source codes.