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1h
comment Strange integration
which version are you using? on V10.01, I do not get 1/2 (-HarmonicNumber[-I] - HarmonicNumber[I]), but only Recursion depth. btw, doing NIntegrate[...] works and gives -0.396291 + 1.65436*10^-24 I which is the correct numerical value that you show there. screen shot: !Mathematica graphics
2h
answered Replace list of symbols in an expression
3h
answered Conditional combining of nested lists
4h
revised Partial fraction decomposition of 1/(e^x-1)
typos
4h
answered Partial fraction decomposition of 1/(e^x-1)
6h
comment Exclude Infinite Value in Table
It works if you add -1. DeleteCases[{1, {2, Infinity}, 3, {4, 1/0}}, Infinity | ComplexInfinity, -1] gives {1, {2}, 3, {4}}
6h
comment How to rotate the Axislabel to parallel with the axis in BarChart3D?
please post a minimal not working example.
6h
comment Exclude Infinite Value in Table
Is there any way to tell Mathematica to skip Table values based on some rule? how about DeleteCases ? Example: DeleteCases[{1, 2, Infinity, 3, 4}, Infinity] gives {1, 2, 3, 4} or DeleteCases[{1, 2, Infinity, 3, 4, 1/0}, Infinity | ComplexInfinity]
7h
answered NDSolveValue with a multiple variable equation
1d
comment How to find all roots of a complex number
Can also just use Solve[x^4 == 1 - I, x]
1d
comment Why does my code produce NDSolveValue::ndnum?
It works for me on V10: !Mathematica graphics try rebooting Mathematica to clear things.
1d
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.
1d
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.
1d
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
1d
revised Manipulate showing the trajectory of a particle
added 63 characters in body
1d
answered Manipulate showing the trajectory of a particle
1d
answered `Solve` with variables as single vector
1d
answered `Solve` with variables as single vector
1d
answered Using conditionals to check if LinearSolve found a solution
1d
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?