My packages Qwt5 and pyqwt5 will be removed with the removal of Qt4 from Debian and yesterday I was looking at the
reverse dependencies and a few of the packages have maintainers on this list.
$ apt-cache rdepends libqwt5-qt4
As a replacement for Qwt5, Qwt version 6 was released many years ago and has been packaged
for debian nearly as long.
As a replacement for pyqwt5 I want to suggest my wrapper, PyQt-Qwt
It is not yet packaged for Debian but I might start packaging it if somebody shows interest.