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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.
Oct
12
comment Why this gives 0?
Can you explain why the result should be sinh(x)? Lets assume all is perfect, and so InverseFourierTransform[FourierTransform[Cosh[t]]] should in theory return back Cosh[t], right? (inverse(fourier(foo))) is foo. Then why is I*Cosh[h]=Sinh[x]? Where did this come from?
Oct
12
comment How to export a text into eps without splitting
it works fine for me. Version 10.01 on windows.
Oct
12
answered StateResponse is non-deterministic
Oct
11
comment How do I find the expression for where the first derivative equals 0?
Mathematica does not have Sqr function. !Mathematica graphics I am using V 10.01
Oct
11
answered Plot Complex Function
Oct
10
comment Epilog with text not shown
You are telling it to put the text at {-12,10} but you are saying the plot range should be {-10,10} ? So it will not show up. Try Plot[x^2, {x, -13, 10}, Frame -> True, Epilog -> {Text[Style["S", FontFamily -> "Helvetica", Black, Bold, 20], {-12, 10}]}]
Oct
10
comment Convert matrix of strings to matrix of numbers
s = {"425060", "0.214235E+07", "0.48", "0.01", "0.39", "0.49", "0.01", "0.38", "1.64", "-1.65", "-2.13", "518"}; InternalStringToDouble[#] & /@ s`, see mathematica.stackexchange.com/questions/1737/…
Oct
10
answered what to do when NSolve does not solve
Oct
10
comment Getting unwanted solution from Solve
Solution 3 is a result of solution 2 I do not understand what this means. Each one is an independent solution. You do not obtain one solution from another? Solution 4th is correct. Try: vars = {x[1], x[2], x[3], x[4], x[5], x[6], x[7]}; eqs = {x[7] == 0, 6 x[4] x[5] + 6 x[3] x[5] x[6] + z*x[4] x[7]^2 + z*x[4] x[5] x[7]^2 == 0}; sol = Solve[eqs, vars]; eqs /. sol[[4]] and this gives True. If you want solution over reals only, add the options Reals
Oct
9
answered Total by a criteria
Oct
9
comment Importing multiple files with a loop
what is the first file name? is it datafile.20.0000.out? so what is the last file full name? is it datafile.20.1010.out ? You can't have an index that is not discrete. So index 20.1 will not work.
Oct
9
comment Importing data from Matlab, using data in “NSolve” and send the results back to Matlab
try matlink matlink.org
Oct
8
comment Converting image data to array
use the ImageData[] command img=Import["ExampleData/lena.tif"]; data=ImageData[img];
Oct
8
comment Matrix Rational Canonical Form
@Ryker this was over a year ago. So I do not remember now. But feel free to try it, and you find a bug you can report it and will try to fix it. Make sure to include the input and the expected output to help me fix it. As far as I know the code is supposed to work ok.
Oct
8
revised Using mathematica to understand linear algebra
added color
Oct
8
comment Using mathematica to understand linear algebra
@ybeltukov thanks for the hint. I changed the point to sphere. yes, it looks better.