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Oct
1
comment Controlling PointSize in a RegionPlot
(+1) Maybe you can include a comment regarding the difference between Point in a RegionPlot and in Graphics: the ability to include Point in RegionPlot as done in the question is due to the fact that Point can be interpreted as a "region" just like e.g. a Disk can. But in that interpretation (which depends entirely on the context being RegionPlot), it's impossible to use styling the way one expects it to work for the Graphics primitive Point. These are basically two different incarnations of Point, and the styling only works when removing it as a RegionPlot argument.
Sep
30
comment How to get `Series` to recognize user-defined function has pole
You reference to Gamma is confusing because it doesn't actually do what you seem to be asking for in the question. E.g., Gamma[1/3] doesn't evaluate even though the argument is numeric. Obviously your question wants that to evaluate, too. So I don't know what the real goal is.
Sep
29
comment What is the recommended way to define numeric function with special cases?
@RunnyKine OK thanks, I edited that in as well...
Sep
29
comment What is the recommended way to define numeric function with special cases?
@MichaelE2 Thanks, I added that info.
Sep
29
comment What is the recommended way to define numeric function with special cases?
@LeonidShifrin and @Daniel Thanks for explanation! I would by default also prefer Piecewise, but was thinking there must also be examples where If could be better (e.g. if one really wants to prevent even symbolic evaluation of one alternative under all circumstances).
Sep
28
comment What is the recommended way to define numeric function with special cases?
I really think the question needs to be made more precise. First of all, the definitions in the example are contradictory. Second, what do you want to do with the function?
Sep
28
comment What is the recommended way to define numeric function with special cases?
@LeonidShifrin Do you really think If is inferior when it concerns purely numeric functions? I wonder why that would be the case. Of course it's not usually equally aesthetic, but is there another reason you're thinking about? I guess the question doesn't really define the functions as purely numeric, so you're right if one admits that symbolic simplifications could still be performed. Thinking about it, it would be best if the question were made more specific.
Sep
28
comment Smoothing a single rectangular pulse in NDSolve
Closely related: A: NDSolve for PDE with discontinuous initial/terminal condition
Sep
27
comment Orthogonal vector in two dimensions
I think it's OK to leave this as a valid question - but only after changing the wording to clarify what "hat vector" means here.
Sep
27
comment Fitting ellipse to 5 given points on the plane
@MarkMcClure Looks like your assumption is correct (of course I already upvoted your answer).
Sep
27
comment Fitting ellipse to 5 given points on the plane
@user153012 For more than five points, see my comment to the original question: it becomes a fitting problem that has been asked about before.
Sep
27
comment Fitting ellipse to 5 given points on the plane
This could be considered to be a special case of Fitting points to tilted, off-center ellipse. But it's different in that this question admits a solution that goes through all points.
Sep
27
comment Discrepancy between Mathematica and Fortran expressions — Fortran gives wrong output (C,C++ programmer trying to use Fortran)
This question is not really about Mathematica, and it doesn't specify in what way the output of the Fortran code is different. Do you mean the data type is different, or are you making plots, or are there special values of kx, ky, kz that give different values of Om1... It's impossible to tell what the issue really is.
Sep
25
comment Tube and CapForm
In version 8 the ends are flat in both examples, too. So definitely a bug.
Sep
25
comment Derivatives of Convolutions with Integration by Parts and Delta Functions
Can you define p[x] with some additional lines of code?
Sep
24
comment How to replace the first occurance in an expression instead of replacing all?
Yes, that works. But now you'd have to do the same if it were Times instead of Plus... anyway, you put your finger exactly on the reason why the original didn't work, and changing the attributes is certainly a way to make it work.
Sep
24
comment How to replace the first occurance in an expression instead of replacing all?
It won't work with this example: HoldForm[7 + x + 2 + 4 + x] /. x + a___ -> 4 + a because the order isn't preserved.
Sep
23
comment Elementwise operation, part deux
@DanielLichtblau Ah, so that's why Nike started their "Just Do it" insurgency in 1988! It all makes sense now...
Sep
23
comment Dirac Gamma matrix Algebra in different dimension
Related: Dirac Matrices in Higher Dimensions (Wolfram Demo)
Sep
22
comment Export textanalysis to pdf
This works on Macs, too. Annoyingly, the ImportString trick doesn't work with "PDF" in this example, so "EPS" does indeed seem to be unavoidable.