All integrable Hamiltonian systems are alike, while each nonintegrable one is nonintegrable in its own way
boussinesq flow
Boussinesq flow generated by a heated cylinder, background is temperature.
vfplot \
--verbose \
--width 8in \
--crop 0/0/2in/1in \
--margin 6/6/-0.4 \
--scale 1e-3 \
--iterations 500/5 \
--pen 0.1mm \
--fill darkred \
--length 0/1in \
--cache 512 \
--aspect 4.5 \
--symbol triangle \
--output vfplot.eps \
grd/u.grd grd/v.grd