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Jan
21
comment Problem with dynamic MouseAppearance updating while “MouseDown”
Sorry it won't work for you, but I don't have any better insight into the mouse appearance while it's being pressed. I tried using the drag event instead, but that didn't work either (for mouse appearance).
Jan
21
comment How to make MousePosition more reliable
@einbandi Yes, I think it happens more easily if I'm right below the box and then enter is slowly... but jVincent's comment about zoom level does seem to apply to me, too.
Jan
21
comment How to make MousePosition more reliable
@jVincent Yes indeed, although I had 100% zoom in the notebook, I had a Magnification setting of 1.25 in the Advanced Global Preferences. When I set that to 1, I don't get the flaky behavior anymore. That's an important clue.
Jan
21
comment How to make MousePosition more reliable
@Silvia So either it's Mac specific, or worse: hardware specific. I'm on a new Macbook Pro with retina display and NVidia Graphics card.
Jan
20
comment Plotting a function, x = 1024
What I saw is just what @VF1 already wrote... and in addition it also works with Plot[s12/.x->y,{y,0,1030}]
Jan
20
comment Plotting a function, x = 1024
The fact that f[x_] works but s12 doesn't leads me to suspect that it's important for Plot to not evaluate the expression too early. E.g., if I replace f[x] by Evaluate[f[x]] in Plot, the error re-appears. But what is happening with the unevaluated expression? One thing it could be doing is some pre-processing for PlotLegends. And coincidentally, that's exactly what has changed in version 9. So I'm inclined to blame PlotLegends. Again!? Or should I blame units support... I like that idea too...
Jan
20
comment Plotting a function, x = 1024
It works without change to the expression if I set f[x_]=s12 and do Plot[f[x],{x,0,1030}].
Jan
20
comment LayeredGraphPlot: two instances of the same label
However, this doesn't return a Graphics object as does LayeredGraphPlot. And of course the styling options are different for Graph, so it will take a bit more work to make this a drop-in replacement.
Jan
20
comment Solving the wave PDE using the Fourier method
Right, that was probably an oversight in the original Piecewise...
Jan
20
comment How to identify patterns in a tensor-polynomial and replace appropriate symbol?
Thanks - in the docs for CoefficientRules it says that the whole thing "works whether or not poly is explicitly given in expanded form." Of course the other answers would also work if you explicitly use Expand first, but in the polynomial manipulation functions that's built in...
Jan
20
comment Solving the wave PDE using the Fourier method
+1 for adding the speed hint. To be more pedagogical, it's worth pointing out that the definition of a[k_] was OK in principle, except for the little difference between := and =. In this case, all that was needed is to use the latter (Set) to get the same speedup that you achieved by copying and pasting into the definition of a[k_].
Jan
20
comment LayeredGraphPlot: two instances of the same label
@Szabolcs Sure, that works too. My rationale was to move the "default" state completely into the rendering function.
Jan
20
comment How to identify patterns in a tensor-polynomial and replace appropriate symbol?
Nice and short. The only way I could trip it up was by leaving a power in symbolic form, as in r[i]^n. That's probably not going to happen, though...
Jan
20
comment Label area on plot
@rm-rf Thanks - and spinut, I'm glad it helped.
Jan
20
comment How can I solve this PDE with initial conditions?
@Silvia That's a valid question - but for now the only answer seems to be: it just can't be done. At least looking at the DSolve documentation, it states that the acceptable form for PDEs is only DSolve[eqn, y, {x1, x2, ...}] and not DSolve[{eqn1, eqn2 ...}, y, {x1, x2, ...}] with multiple equations as would be the use case here.
Jan
20
comment How to identify patterns in a tensor-polynomial and replace appropriate symbol?
+1 But I just noticed it doesn't work if there's a constant term, as in 1 + r[i] ...
Jan
20
comment Why does Simplify ignore an assumption?
@NickStranniy That could very well be where I first read about this problem, too. Thanks for the link!
Jan
19
comment How can I solve this PDE with initial conditions?
@Silvia That notation doesn't really matter (OK, one has to add /.t->0 in his approach, but it's not the main problem). I feel tempted to answer, but it looks a lot like a homework problem. As a hint: first solve without the initial conditions, leading to two functions C[1] and C[2]. Then find those functions by imposing the initial conditions at t = 0. This can be done by converting both conditions to a set of equations only involving C'[i] at x and -x.
Jan
19
comment Complex Region using Presentations Package
I don't have the package (heard only good things about it!) but from looking at your syntax my guess would be: the first argument in ComplexRegionDraw[Exp[z]... has to be a boolean condition, not a complex function. Therefore, you should replace that by Abs[Exp[z]]<1, or Re[Exp[z]]>0, or some condition along those lines.
Jan
18
comment Label area on plot
Related question: Scale Insetted Characters to Plot