How to find the difference between 2 lists in XSB Prolog?

We define the difference between two lists A and B as A-B = Elements in A but not B. SWI Prolog has a builtin predicate to do this in the form of subtract/3. It seems that XSB Prolog lacks this predicate. So, here is a simple alternate definition of subtract in XSB prolog- subtract(A,B,C):- findall(X, (member(X,A), not(member(X,B))), C). where … More How to find the difference between 2 lists in XSB Prolog?

The region controller does not know whether any boot images have been imported yet-Ubuntu MAAS error solution

After setting up the web interface for Ubuntu MAAS, I tried importing boot images into the cluster through the GUI. And the below message popped up and never went away- The region controller does not know whether any boot images have been imported yet. If this message does not disappear in 5 minutes, there may … More The region controller does not know whether any boot images have been imported yet-Ubuntu MAAS error solution

Solution to Ubuntu MAAS Internal Server Error: 500

After installing Ubuntu Server and the MAAS packages, I set up the web interface of MAAS @ http://XX.XXX.XXX.XXX/MAAS. My N/W was configured with DHCP. I restarted my machine and started hitting the error. Internal Server Error The server encountered an internal error or misconfiguration and was unable to complete your request. Please contact the server … More Solution to Ubuntu MAAS Internal Server Error: 500

Religion vs Science

Most wars have been fought in the name of religion. It is a tool used by rulers from eons to keep the masses under control. But Religion found its nemesis in Science which has been steadily denting the religious structures. But will religion give up? Will it join hands with the enemy to ensure its … More Religion vs Science