Where are GUI apps for ports installed?

[Jerry]

Some ports install a double-clickable binary in /Applications/MacPorts. 

However, the only things installed in that location are on my system are AquaTerm, Pallet, some python 2.7 auxiliary stuff, and something related to Qt4 called qmlplugindump.

I have the Spyder port installed and there is a binary for it but it does not install in this location but rather apparently in

/opt/local/Library/Frameworks/Python.framework/Versions/2.7/Resources/Python.app/Contents/MacOS/Python

with a symlink in /opt/local/bin to another small file which is a short python script which launches it.

A different situation is cmake. When I install this from another place (probably the official cmake developer site), there is a GUI application placed in /Applications. However, the MacPorts version apparently does not install a GUI app anywhere.

I find this a little disconcerting. Is there a MacPorts policy about these kinds of things?

Jerry