Nasser
Reputation
34,893
95/100 score
 Oct 21 comment How to find all roots of a complex number Can also just use Solve[x^4 == 1 - I, x] Oct 20 comment Find all roots in range Does Solve[Zeta[1/2 + I y] == 0 && 0 < Abs@y < 100, y, Complexes] give same result as your method? For numerical, one can always throw N on it with some precision value as needed? I did not compare if this gives same results as what you have. Oct 20 comment Why doesn't FullSimplify simplify expressions with DiracDelta? may be because it does not know if x>y? Assuming[x > 0 && y > 0 && x > y, FullSimplify[x/y DiracDelta[x - y]]] gives zero. (I assume you are looking for zero as answer.) The point is, just telling M that x>0 and y>0, does not say anything about if x==y or not. Oct 20 comment Find all roots in range Solve works also: Solve[Zeta[1/2 + I y] == 0 && -10 < Abs@y < 10, y, Complexes] gives {{y -> (5 I)/2}, {y -> (9 I)/2}, {y -> (13 I)/2}, {y -> (17 I)/2}} So does NSolve Oct 20 revised Manipulate showing the trajectory of a particle added 63 characters in body Oct 20 answered Manipulate showing the trajectory of a particle Oct 20 answered Solve with variables as single vector Oct 20 answered Solve with variables as single vector Oct 20 answered Using conditionals to check if LinearSolve found a solution Oct 20 comment Using conditionals to check if LinearSolve found a solution can you post an example where LinearSolve[A,b] returns LinearSolve[A,b] and nothing else? Oct 20 comment DSolve will not apply assumption m ∈ Integers I do not think DSolve uses/accepts user assumptions. This was my understanding all along. Unless something changed in newer version of M. Oct 20 answered Problem in downloading “ToMatLab” package Oct 19 comment Derivative of an expression containing a symbolic sum so there is going to be a term in the series in the denominator where \[Alpha]=\[Beta] This I do not understand at all. You are doing symbolic differentiation? How is Mathematica supposed to know that Alpha and Beta are the same symbol at one point? Oct 19 comment Derivative of an expression containing a symbolic sum appears explicitly in the numerator, and implicitly in the denominator due to the sum I do not see it. The denominator has no Subscript[\[Lambda], \[Alpha]] in it at all. The sum is over beta, not alpha. Here is screen shot of your expression !Mathematica graphics Oct 15 awarded Necromancer Oct 12 comment StateResponse is non-deterministic @Mathxy btw, It might be a good idea to send this to support@wolfram.com. Oct 12 comment StateResponse is non-deterministic @Mathxy As I said, I do not know internally what happens. CLearly this is a bug, but you asked for a workaround. There was some changes in v10 with processing of diracdelta's in control system. May be this is related. See mathematica.stackexchange.com/questions/57891/… Oct 12 comment Why this gives 0? @Anixx that is correct, that is why I used ExpToTrig to make it generate a result. Ofcourse Exp[t] and ExpToTrig[Exp[t]] are the same thing, mathematically speaking. But one gives a result and one does not. That is why. Just to see the zero come out. Else will not see it. Oct 12 answered Why this gives 0? Oct 12 comment Why this gives 0? I did not notice the /w. But still, I do not see how it the final result should be Sinh[x]. I think the 0 is not correct and I know why it does it, but I do not see how you came up with Sinh[x] either. But not important. I think 0 is not correct.