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Jul
28
comment why the variable scope is not local when using evaluate to plot multicurve?
For this reason it is better to use the option Evaluated -> True instead of Evaluate
Jul
28
comment Interpolation function rejected by ParametricPlot3D
I think it is just an accident that Mathematica manages to correctly interpret the unsupported syntax in some cases.
Jul
28
comment Interpolation function rejected by ParametricPlot3D
y[t] /. bally is a list. Use y[t] /. First[bally] to extract the actual interpolating function.
Jul
26
comment Possible bug in Dynamic
+1 Nice troubleshooting. Wrapping the ContourPlot in PreemptProtect seems to work too.
Jul
26
comment TrueQ returning False on true statement
TrueQ[Log[2]/Log[8] == 1/3] returns True with version 10 on Windows 7.
Jul
24
comment Is there a way to recreate the typical Red/Blue-Postereffect using Mathematica?
@rm-rf, oh - so I did. Thanks.
Jul
24
comment Mapping with Trace[]
{r1, r2} is evaluated first, so the symbols are replaced by their values before Trace sees them.
Jul
24
comment Is there a way to use video codecs for avi files in Mathematica?
g3kk0, just to be clear, are you saying that you get uncompressed AVI regardless of which codec you select? This is (obviously) incorrect behaviour - I suggest stating your OS and QuickTime version in the question so that others with the same setup can comment on whether they see the same problem.
Jul
24
comment Is there a way to use video codecs for avi files in Mathematica?
@Mr.Wizard, annoyingly there is support in Media Foundation for an AVI media sink but only for Windows 8.1.
Jul
22
comment Is there a way to use video codecs for avi files in Mathematica?
@Mr.Wizard, actually my library will import AVI files but not export them.
Jul
22
comment Find sublists of a list that match some conditions
Ah, of course! I feel silly now :-)
Jul
21
comment How can I prevent a compiled function from using uncompiled evaluation?
@JasonB, please add that solution as an answer - it is valuable and shouldn't be hidden away in a comment.
Jul
21
comment Why do quote marks appear in output when saved with Save Selection As?
Strange. I get the quotes if I select the cell contents but not if I select the cell bracket.
Jul
21
comment Can't plot rotated region
@user21, email sent.
Jul
21
comment Invert 3D objects (shape) to 3D patterns objects (shape)?
The RegionPlot3D example in your comment is very easily inverted. The region function r[x,y,z] simply returns True or False according to whether the point {x,y,z} is inside the region or not. So to invert the volume you just need the boolean Not operation, i.e. use RegionPlot3D[ !r[x, y, z], ...]
Jul
21
comment Invert 3D objects (shape) to 3D patterns objects (shape)?
The example in your question is rather unclear, because SphericalPlot3D plots a 2D surface embedded in a 3D space. You may choose to conceptualise this surface as the interface between a solid volume and a void, but then the inversion won't change anything - the surface separating the solid from the void remains the same.
Jul
19
comment Can't plot rotated region
For me even the first basic example in the TransformedRegion documentation doesn't work properly. And the second example hangs the kernel...
Jul
19
comment DeleteDuplicatesBy is not performing as I'd hoped. Am I missing something?
I note that for an association argument there are four conversions!: assoc -> list -> assoc -> list -> assoc
Jul
19
comment Excluding region with `RegionDifference`
The first time I tried it, it crashed the kernel. The second time I got the correct result. Windows 7, v10.0
Jul
18
comment How can I plot a Chebyshev spiral?
PolarPlot[Evaluate@Table[n+ChebyshevT[n,t/Pi-1],{n,0,20,2}],{t,0,2Pi}]