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Dec
7
comment How to get StreamPlot to draw many hundreds of streamlines?
Actually, the uniform spacing between streamlines that you like so much isn't really that useful. In many applications, one wants the streamline density to vary with the field strength. The automatic minimum distance actually prevents that! So I find it necessary to choose my own seed points to make sure that the function is represented faithfully. When you ask for longer streamlines, it becomes harder on average to enforce a minimum separation, and spacings that look even in one region may not in another region.
Dec
7
comment How to get StreamPlot to draw many hundreds of streamlines?
The spacing depends only on your choice of seed points.
Dec
7
comment How to get StreamPlot to draw many hundreds of streamlines?
Interesting observation (+1).
Dec
7
comment How to get StreamPlot to draw many hundreds of streamlines?
@RahulNarain OK, this really is a different problem then. I'll edit my answer to address this shortcoming.
Dec
7
comment How to use $\LaTeX$ for typesetting labels and titles in Mathematica
possible duplicate of Create complicated text formulas in graphics
Dec
6
comment Mathematica won't solve equation I know is solvable
Yes, you can handle the radial equation numerically with NDSolve and the new parametric functionality. If the question is asking for analytical solutions, then it's much more difficult, see @acl's comment above. One would have to do at least some of the separation steps by hand. I guess that means we still need textbooks...
Dec
6
comment How to keep Collect[] result in order?
@user15964 Yes, I think my statement about HoldForm is confusing. I think I wanted to say that it's not needed if you want to replace a list by a sum, but of course it's needed to preserve the desired order as I tried to say afterwards. I'll edit this, but you should delete your answer because you're not supposed to write follow-up questions that way.
Dec
6
comment Formula Formatting is Small and Chunky?
@cartonn Maybe - but the screenshot part is an external process, so it may be a bit off-topic. Anyway, this other question could be worth mentioning in this context too.
Dec
6
comment Prevent manipulations in PlotLegends
Good idea to use Hold (+1). My answer is more boring and I don't actually have a way to test it...
Dec
5
comment ListPointPlot3d to visualize points close to a manifold
Although the title doesn't mention it, this seems to be about fitting a surface to a point list. If so, it's a possible duplicate of Construct a simple mesh or tetrahedral mesh from 3D image surface
Dec
5
comment Make a slider controlling a generated character's code value
But your example code does not contain any variable a! What is the variable a, and what is it supposed to be changed to?
Dec
4
comment Circular AngularGauge does not roll over boundaries
I know this isn't an answer, but personally I would just draw it from scratch... My comment is mainly caused by indignation about having the System context bloated by such unnecessary functions.
Dec
4
comment Use elements of Array inside function definition
Or he could define myF = v.(1/Range[Length[v]]) and call myF[[i]] instead of myF[i].
Dec
4
comment How to Clear variables with apostrophe?
Yes, that's true - as long as you're OK with the fact that your \[Prime] doesn't appear raised above the text baseline. I.e., \[Prime] doesn't actually look like the character you'd usually call an apostrophe (and it doesn't look like the one displayed in this answer). The unicode character that I found has this raised appearance.
Dec
3
comment Is there a way to run Python from within Mathematica?
@MarkMcClure You're right, I think that's an excellent answer then.
Dec
3
comment Is there a way to run Python from within Mathematica?
@MarkMcClure I think Pythonika is the reverse of the reverse, and he's only asking for the reverse...
Dec
3
comment Is there a way to run Python from within Mathematica?
I've given some answers where a Python script was assembled and then executed from within a notebook: here and here
Dec
3
comment How to define a differential operator?
A closely related question is Having the derivative be an operator
Dec
2
comment I need to multiply a series of matrices
@NasserM.Abbasi lol, it's too late at night here...
Dec
2
comment I need to multiply a series of matrices
Yes, you could also take a List and change its head to Times if you want to get the normal multiplication of all elements in a list. But just to clarify: Dot is really very different from Times because conventional matrix multiplication is not commutative, whereas Times doesn't care about the order of the factors. BTW - strange that @NasserM.Abbasi appears here as your name. That's not you, right?