Hi Tony,as far as I know the message is correct. I had the same problem some time ago. There is no simple solution at the horizon. The best recommendation would be, to to make friends with other formats like png or pdf.
I had searched through several forums on qt. The support of Postcript output was discussed and some of the developpers clearly expressed that Postcript will not be supported any more in future. I cannot simply find the links - just remebering in this as a fact.
With linux there is a partial solution to keep eps-output. Most systems, i.e. linux destributions, still deliver qt4. One may install both, qt4 and qt5, in parallel. Qt4 supports eps-output. I am pretty sure, this is also possible for MacOS, but I cannot tell you how. Here you need to ask a Mac-wizzard. The next thing would be to change pyferret a little bit. There are several python scripts (.py-files), importing either PyQt4 or PyQt5. If there is PyQt5 installed, it would be preferred. You would have to edit these files to import the PyQt4 module in any case. Just a few lines to modify. Even possible without any python knowledge. If you need more details I could help, but in this case please wait until next Tuesday. So your turn would be to learn, how to keep qt4 and qt5 in parallel on your Mac, no need to downgrade.
Best, Martin Am 20.04.2019 um 12:24 schrieb Jian (Tony) Ma:
Dear All, I got problem with PyFerret on Mac. When I use frame/file=1.eps, it tells me there is no postscriptformat for QPrinter. I searched online and found this is a problem with qt5, but I cannot downgrade to pyqt4. Any solution? Frustrated! Thanks, Tony Sent from my iPhone