Astronomical Applications Department, U.S. Naval Observatory - NOVASC (Page 3)

concerned with the details of the geometry or physical models involved in the computation.

The NOVAS-C source code contains sufficient internal documentation to make the usage clear.

Expanded explanations of a few of the most frequently-called functions are given elsewhere in this
document. In the Fortran version of NOVAS, some of the basic- and utility-level subroutines are provided
in several versions to accommodate users with a need for alternative algorithms. The C version differs from
the Fortran version in this regard: only the "standard" version of each algorithm is provided. However,
two versions of the software that provides basic lunar and planetary ephemeris data are included.

The next section of this document (Section 2) provides an overview of the files that constitute NOVAS-

C. This section also provides simple instructions for installing and checking the software. Section 3
provides a list and brief description of each NOVAS-C function. Section 4 gives detailed descriptions of a
few of the most frequently-called functions. Throughout this document, bold text will be used to refer to
file names and italic text will be used to refer to function or subroutine names. Variable names or code
snippets will be presented in a

typewriter-like

font.

Also, be aware that the U. S. Naval Observatory's Astronomical Application Department maintains a

NOVAS page on the World Wide Web. It can be reached via the USNO home page
(http://www.usno.navy.mil).