Hi Marco,I had the same problem. The different Linux flavours tend to advance different libraries with different speed. Ubuntu is different from suse or redhat. This limits portability, as you see, but the interests of people are widespread. Some need stable tools and do not care, how results are produced. Others need the latest twist of a library and advance software development rapidly.
You may try to generate a fake png15-library just linking libpng16 to the name of libpng15. This MAY work or may not. Be careful not to destroy your system: Link or better copy the library to some directory outside of the system and set the LD_LIBRARY_PATH to this directory. If it does not work, the link can be simply deleted.
For suse linux this method did not work. My way out is to compile pyferret by myself from source. Karl's cookbook how to do this is excellent. But most probably it is not required to build all the libraries from Cairo to netcdf by yourself. Most of them will be in the ubuntu-distribution When installing, please be aware, you have to install not only the libraries but also the development packages.
Hope this helps. Best, Martin On 07/19/2017 03:36 PM, Marco van Hulten wrote:
Hello, In installed PyFerret, following http://ferret.pmel.noaa.gov/Ferret/documentation/pyferret/build-install I get an error concerning libpng: $ pyferret -version Traceback (most recent call last): File "<string>", line 1, in <module> File "/home/mhu027/installed/pyferret/lib/python2.7/site-packages/pyferret/__init__.py", line 44, in <module> from pyferret import libpyferret ImportError: libpng15.so.15: cannot open shared object file: No such file or directory I am using Ubuntu 16.04, which only provides libpng12 and libpng16. Maybe PyFerret could be more lenient and check for libpng>=15 (or whatever is minimally needed)? - Marco