I've installed GraphicsMagick following the instructions on the website, and ran the build verifications it says, and though I'm not sure if those were to verify that install was successful or not, but at I guess at least having terminal to recognize the gm command means it was successfully installed, and besides I found a GraphicsMagick directory in my
/usr/local/include, again I don't know if that proves anything. But when I list the installed packages with dpkg -l it's not there.
Now, I need to install Octave and I wonder if it will install GraphicksMagick again, which is something I don't want it to do if it ever would. Besides I am now unable to remove it using apt-get remove. So how can I know what's wrong with my installation and if installing Octave will install its own version of GM?