Variable or compound expression - unification algorithm, Computer Engineering

Variable or compound expression - Unification algorithm:

Here some things to note regarding this method are: 

(i) There if really trying to match a constant to a different constant fails this means that they are not equal, neither is a variable or compound expression or in list also. However if we considered none of the cases in unify_internal is true to must return failure.  

(ii) In case 1 and 2 in  unify_variable(var,x,my)  check and finds neither inputs have already been substituted. However if we considered if  x  already has a substitution value and var, rather than x and var so there it does similarly if var already has a substitution. 

(iii) In case 3 we see that in  unify_variable  is called as the  occurs-check  case or occur-check. However if we considered this is important to visualize we got to the stage when to complete a unification if we required to substitute X into say, f(X,Y). However if we considered we would write  f(X,Y)  instead of X. After than this still has an  X  in it! Thus we would use to substitute  X  by  f(X,Y)  and again giving us as:  f(f(X,Y),Y)  so it  is obvious why we should never have tried this substitution in the first placeis means that this process will never end. However the occurs check makes sure this isn't going to happen before case 4 returns a substitution. But in realty the rule is:; that you cannot substitute a compound  for a variable so such variable appears in the compound already that you will never get rid of the variable. 

(iv) However if we considered unify_internal(op(x),op(y),mu)) a part of case 5 in unify_internal checks whether the operators of the two compound expressions are the same. Just because of it will return false if, considered an example where it tries to unify two predicates into different names or a  with symbol.

Posted Date: 1/11/2013 6:24:34 AM | Location : United States







Related Discussions:- Variable or compound expression - unification algorithm, Assignment Help, Ask Question on Variable or compound expression - unification algorithm, Get Answer, Expert's Help, Variable or compound expression - unification algorithm Discussions

Write discussion on Variable or compound expression - unification algorithm
Your posts are moderated
Related Questions
Explain the term - Integrity In most cases, corporate data should remain unchanged by third parties, so the system should be capable of ensuring that only authorised personn

Difference between blocking and non-blocking Verilog  language  has  two  forms  of  the  procedural  assignment  statement:  blocking  and  nonblocking. The two are distinguis

Illustrates about Metal Fix. A Metal Fix implies that only the upper metal interconnects layers are influenced. Connections may be made or broken, but new cells may not be adde

What is a 3-D Accelerator?  3-D Accelerator is no magic technology. It is merely an accelerator chip which has built-in ability to perform the mathematics and algorithms neede

What is an I/O buffer? What is the advantage of buffering? Is buffering always effective? Justify your answer with help of an example.   One type of I/O requirement arises from


How are the function code handles in Flow Logic? When the User selects a function in a transaction, the system copies the function code into a           specially   designated

Define class NP. Problems that can be solved in polynomial time by a nondeterministic TM. Contains all problems   in P and some problems possibly outside P.

Q. Explain the following: a) Gray code b) Parity code c) Overflow Q. Give the counting up to 30 in Base 5. Q. Convert (175.6)8 into Gray code and Excess-3 code.

First, remember that different processes keep their own data in distinct address spaces. Threads, on the other hand, explicitly share their entire address space with one another. A