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Mar
26
comment How can I name “a[[i]]” the parts of Table “a”? Or how to make Table “a” grow inside FindMinimum?
(+1) that's the cleanest solution (I think Mathematica used to be unable to do this, but it got cleverer...)
Mar
26
answered How can I name “a[[i]]” the parts of Table “a”? Or how to make Table “a” grow inside FindMinimum?
Mar
26
comment Adding and subtracting from elements in a list
@Mr.Wizard Sure, I just didn't want to copy you (already upvoted your answer, of course)... and maybe Outer is helpful because you can generalize it to construct other matrices.
Mar
26
revised Adding and subtracting from elements in a list
edited title
Mar
26
answered Adding and subtracting from elements in a list
Mar
25
awarded  Custodian
Mar
25
reviewed Close How to get complement from two matrices?
Mar
25
awarded  Enlightened
Mar
25
awarded  Nice Answer
Mar
25
reviewed Approve suggested edit on Why does simplification in Mathematica depend on variable names
Mar
25
comment Why does simplification in Mathematica depend on variable names
I attempted an explanation of this phenomenon in this related post
Mar
25
comment Fortran kind of matrix creation
Are you sure you want the inner If in terms of i, j - and not in terms of ix, iy, jx, jy? The latter seems more natural and would probably make it easier to write this in a more Mathematica friendly way.
Mar
25
comment NDSolve does not respond
@OleksandrR. I don't know if this answers your question, but the reason FindRoot or something like it comes into play is this: the first-order DAE is equivalent to a second-order differential equation obtained by taking $d/dt$ on both sides. Since the order increased, we need an additional initial condition (for Vo'[0]). But the latter is not at our disposal because the original DAE fixes it via the value of V which got killed in the $d/dt$. This is where FindRoot comes in to determine what the correct Vo'[0] is. Then the 2nd order diff. eqn. can be solved as usual.
Mar
25
comment How to simplify expressions containing derivatives
But then the title of the question should be different.
Mar
25
comment How to simplify expressions containing derivatives
You should spend some time writing a small example in valid Mathematica code so that we can see what your starting point is. Otherwise we'd have to waste time guessing wether some or all of the f, g, h are defined or not, whether x is the independent variable, etc.
Mar
24
comment Plotting a large number of data points
@cormullion I looked up the guideline on downvoting, and near the bottom it mentions that it should be used in extreme cases only. This question seems quite innocent to me.
Mar
24
revised Plotting a large number of data points
added 258 characters in body
Mar
24
answered Plotting a large number of data points
Mar
24
comment Finding Limits in several variables
I see - and had a look at the paper you referenced. Seems like Maple wasn't able to do that limit either...
Mar
23
awarded  Enlightened