Difference between fsolve and nSolve? [CAS]

[John Colvin]

(04-05-2015 08:26 PM)mandresve Wrote:  Hi to everyone...

Recently I had a conflict understanding the fsolve and nSolve functions in my Prime.

I wonder what is the difference between them? in the catalog's description, the explanation for both functions appears exactly the same. When I solve a function for x (or whatever numeric constant/var), sometimes it works better with nSolve than fsolve, of course, entering the required parameters for each command to its solution.

I will be very grateful if someone give me examples of cases in which I can or cannot use fsolve and in which types of equations is best to use nSolve.

Thank you very much.

Edit:
If I specify the range of solution that I hope to get (within the fsolve command) I finally get the same response that gives me nSolve, for example using the range 0 to infinity. What is the idea of having two commands? Isn't supposed that if I miss optional fsolve arguments the command must evaluate the expression in any interval? (obviously the guess/interval and the solution method are optional within fsolve). According to my understanding, XCAS documentation shows that fsolve and nSolve commands do exactly the same.

According to the Prime Help, fsolve() takes an optional 4th argument that specifies an iterative algorithm for solving the equation. Otherwise both nsolve and fsolve appear to do the same thing.