19,577 reputation
24092
bio website sites.google.com/a/unca.edu/…
location Asheville, NC
age
visits member for 2 years, 7 months
seen 1 hour ago

I've been a professor of mathematics at The University of North Carolina - Asheville since 1997. I've been using Mathematica since I started graduate school in mathematics at Ohio State in 1989. At that time, we used version 1.1 (as I recall) to teach calculus in our Calculus and Mathematica classes. I've used it pretty much continuously in my teaching and research since then.

In addition to my posts on SE, you can find some of my papers, teaching notebooks and other Mathematica based oddities strewn throughout my website.

In recent years, I've also worked as a part-time consultant to Wolfram Research focusing on development of mathematical content for WolframAlpha.


Mar
6
comment How to visualize slope fields of differential equations without vectors?
Well, "slightly off" would be a better description than "poor". :)
Mar
5
comment How to visualize slope fields of differential equations without vectors?
+1 for the VectorStyle->"Segment", which I didn't know. Not actually a slope field, however.
Mar
4
comment Generating high quality charts in Mathematica for use in LaTeX and Word
Looks like a question for the main site, to me - although possibly a duplicate. At any rate, PNG is definitely a raster format - not vector, so that's likely an issue. For nice figures with labels in LaTeX, I usually export to EPS and use the psfrag package in LaTeX to get native fonts in the figures.
Mar
4
comment Plot Matlab icon
Agreed on the boundary constraints. For what it's worth, my image (done quite some time ago) was based on an earlier icon which (as I recall) was constrained at the edges.
Mar
4
comment How to plot data of complex numers
ListLinePlot[{Re[#], Im[#]} & /@ Flatten[K0 /. out]]
Mar
3
comment 2d heat conduction equation: Boundary and initial conditions are inconsistent
@george2079 The new reference site is set up to hold lots of new information of finite element methods. Most of these pages don't yet exist, but presumably will in the near future: reference.wolfram.com/search/?q=fem
Mar
3
comment 2d heat conduction equation: Boundary and initial conditions are inconsistent
It's possible that the techniques outlined in the answer to this question might help.
Mar
1
comment StreamPlot for Bifurcation Diagram
@Amzoti I also just noticed that you asked about the GIF, so I added that as well.
Mar
1
comment StreamPlot for Bifurcation Diagram
@Amzoti Glad you like it! I've added just a little commentary that might explain a few things. Have fun!
Feb
28
comment Third argument of Compile
Good question! I consider myself pretty good at using Compile but find the third argument to be a by mysterious.
Feb
28
comment Plot Matlab icon
@xzczd Thanks! Glad you liked it.
Feb
27
comment Finding a number which has the same remainder when dividing certain other numbers
@shrx Taste? I personally find n=n+1 to be a bit more clear. I am aware that a good C compiler will replace n=n+1 with n++ but I think there's not much difference in Mathematica. If anything, n=n+1 is very slightly faster.
Feb
27
comment Plot Matlab icon
Very nice! I don't know that LaplacianFilter existed when I first did this. :)
Jan
29
comment Iteration of multiple functions that feed into each other
I recommend you write a single function T[{S_, c_, y_, x_, t_, F_}]] and iterate a few times starting from a list of length 6 using NestList first. As others have observed, there are some questionable points in your function definitions, so I'm hesitant to jump in myself.
Jan
8
comment How to distinguish expression from zero
As stated, your problem is undecidable, according to Richardson's theorem. If you could state your problem more precisely (present your matrix or a small piece of it, for example), then there might be a reasonable approach to your specific problem.
Dec
27
comment Nonrectangular region for NDSolve
I responded yesterday with a similar answer but deleted it when I realized that my approach did not deal correctly with the Neumann type boundary condition at the top. The problem is that your transformation does not preserve orthogonality on the top boundary thus, a Neumann condition in the (x,y) plane doesn't translate to a normal derivative in the (u,v) plane. Furthermore, NDSolve doesn't work when non-normal derivatives are are included as boundary conditions, it issues an NDSolve::bcnorm error. I could temporarily un-delete my answer, if you like.
Dec
27
comment Extract Style Attributes from Style[]
@rm-rf So you'd like Equal[var2,var1] to evaluate to True in the same way that Equal[1,1.0] evaluates. I can see that. But, are there other situations where Equal[a,b] evaluates to True where a and b are non-identical, non-numeric expressions? I'm not sure off the top of my head, but I haven't been thinking about code so much lately. It's a little far afield of the OP's intention, perhaps. :)
Dec
27
comment Extract Style Attributes from Style[]
@rm-rf Isn't there? var2 = Style["aString", Bold, 24]; var1 = Style["aString", FontWeight -> Bold, FontSize -> 24]; OrderedQ[{var2, var1}] returns a reasonable result. Do you want var1 and var2 to be the same?
Dec
27
comment Is it Possible to change dashes into circles with Plot command?
Very nice! One big advantage is that your approach is independent of the AspectRatio of the figure, while mine only works in true aspect ratio, though that shouldn't be hard to adjust. It might be work mentioning that your interpolated function arc has the form arc[s]={x,y}, where s is distance traveled along the arc and {x,y} is the resulting point, i.e. it is exactly the arc length parametrization.
Dec
25
comment Is it Possible to change dashes into circles with Plot command?
Thanks! I was aware of the EllipticE thing, but figured the resulting function would need to be inverted numerically anyway. As I think of it further, perhaps the special function representation arcLength could be passed to InverseFunction or some such? Seems overly mysteriious, though.