Here are a some (well, more than 250) demos.
Much of the low level bit-magic code is shown on the bit wizardry page.
Read the short description, the Linux Software Map (LSM) file fxt.lsm
Generated doc-oids:
aux0-doc.txt auxiliary routines
aux1-doc.txt auxiliary routines for 1-dim arrays
aux2-doc.txt auxiliary routines for 2-dim arrays
bits-doc.txt bit wizardry
bpol-doc.txt binary polynomials and arithmetic over GF(2**n)
comb-doc.txt combinatorics (combinations, partitions etc.)
convolution-doc.txt convolution
mult-doc.txt multiplication of large numbers
correlation-doc.txt correlation
dctdst-doc.txt cosine and sine transforms
ds-doc.txt data structures (FIFO, heap etc.)
fft-doc.txt fast Fourier transforms
realfft-doc.txt real valued FFTs
fht-doc.txt fast Hartley transforms
walsh-doc.txt Walsh transforms
haar-doc.txt Haar transforms
mod-doc.txt modular arithmetics and number theory
ntt.h-doc.txt number theoretic transforms
perm-doc.txt permutations
sort-doc.txt sorting and searching
data-doc.txt tables of mathematical data.
The tables can also be accessed via the mathdata page.
generated index of all docs
The table of contents as text file (generated from dvi):
fxtbook-toc.txt (UTF-8 text)
The change log: fxtbook-changes.txt (ascii text)
fxtbook.dvi.gz (dvi, about 1350kB).
fxtbook.ps.gz (postscript, about 1900kB).
fxtbook.pdf.gz (pdf, about 3000kB).
Last update: 2008-September-09 (22:24)
fxtbook.pdf (UNCOMPRESSED pdf, about 4800kB)
The index as text file (generated from dvi):
fxtbook-idx.txt (UTF-8 text).
List of referenced integer sequences from the On-Line Encyclopedia of Integer Sequences
(OEIS)
as text file (generated from dvi):
fxtbook-oeisref.txt (ascii text).
If you want to set a link to the fxtbook please use http://www.jjj.de/fxt/#fxtbook instead of directly linking to one of the files (e.g. fxtbook.pdf).
An excellent source of FFT- and DSP- related papers is CiteSeer