Fourier Cosine Integral
is a FORTRAN77 library which
implements ACM TOMS algorithm 427, for approximating
a Fourier cosine integral of the form
Integral ( 0 <= T < +oo ) f(t) cos ( w * t ) dt
While the text of many ACM TOMS algorithms is available online
http://www.netlib.org/toms/index.html, most of the early
algorithms are not available. This is one of them. I typed it
value = frcos ( fc, w, t, et, hl )
where FC is a function that evaluates f(t),
W is the multiplier of the argument, T
is the finite upper limit for the integral, ET
is the requested absolute accuracy, and HL is a
limit on step size convergence, such that convergence
in any subinterval is not recognized unless the subinterval
is smaller than HL.
TOMS427 is available in
a FORTRAN77 version.
Algorithm 427: Fourier Cosine Integral,
Communications of the ACM,
Volume 15, Number 5, May 1972, pages 358-360.
Examples and Tests:
List of Routines:
FRCOS approximates a Fourier cosine integral.
You can go up one level to
the FORTRAN77 source codes.
Last revised on 08 December 2005.