8.15 September 17, 2013
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Top new questions this week:
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[Is it possible to use RandomChoice to choose without other choices
being
evaluated?]\url{http://mathematica.stackexchange.com/questions/32175/is-it-
possible-to-use-randomchoice-to-choose-without-other-choices-being-evalu
at}
I'm trying to do this:
i1 = 1;
i2 = 1;
RandomChoice[{
(i1 = i1 + 1),
(i1 = i1 - 1),
(i2 = i1 + 1),
(i2 = i2 - 1)}]
In order to chose randomly which variable is going to be incremented or
...
- asked by Gustavo Bandeira (14 votes), answered by ybeltukov (13 votes)
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[Color Histogram3D by Bin
Location]\url{http://mathematica.stackexchange.com/questions/32460/color-hi
stogram3d-by-bin-location}
I am using a Histogram3D plot to view the correlation of the R & G
of an RGB image. Naturally, I want the bins to have a color
corresponding to their $x$, $y$ (R,G) position on the chart.
...
- asked by Perfect Tommy (11 votes), answered by Kuba (10 votes)
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[Method -> {"AxesInFront" -> False} for
Graphics3D]\url{http://mathematica.stackexchange.com/questions/32168/method
-axesinfront-false-for-graphics3d}
I'm aware of two ways to manage positioning of Axes for Graphics3D:
AxesOrigin and AxesEdge. They seem to be quite different in terms of
what is actually happening:
GraphicsRow[{
...
- asked by Kuba (11 votes), answered by Brett Champion (2 votes)
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[Why does Mathematica return a Fourier transform for a function for
which it is not
defined?]\url{http://mathematica.stackexchange.com/questions/32387/why-does
-mathematica-return-a-fourier-transform-for-a-function-for-which-it-is-n
> }
The following function
$$g(x) = (1 + x^{1/a} )^a $$
should NOT have a Fourier transform, as far as I am aware, for any real
values of $a$ since $g(x)$ is not nice in the sense of decays quickly
...
- asked by Luap Nalehw (10 votes), answered by ybeltukov (11 votes)
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[Find eigen energies of time-independent Schrodinger
equation]\url{http://mathematica.stackexchange.com/questions/32293/find-eig
en-energies-of-time-independent-schrodinger-equation}
I'm trying to get the eigenvalues of a one dimensional time-independent
Schrodinger equation,
$-\frac{h^2}{2m_0}\frac{d^2\psi}{dx^2}+U(x)~\psi=Ei~\psi$
where U(x) is some potential and Ei is the ...
- asked by xslittlegrass (10 votes), answered by Jens (13 votes)
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[Is there a triangle like
this?]\url{http://mathematica.stackexchange.com/questions/32338/is-there-a-
triangle-like-this}
I want to find the numbers $a$, $b$, $c$, $d$ of the function $y =
\dfrac{a x + b}{c x + d}$ so that the triangle $ABC$ with three points
$A$, $B$, $C$ have integer coordinates and lies on the graph ...
- asked by minthao_2011 (8 votes), answered by belisarius (15 votes)
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[Unexpected behaviour of Solve applied to two equations in two
variables]\url{http://mathematica.stackexchange.com/questions/32246/unexpec
ted-behaviour-of-solve-applied-to-two-equations-in-two-variables}
I have a simple Mathematica expression
Solve[{a(a-1)Sqrt[1+a^2+b^2] == b(a^3-1), b(b-1)Sqrt[1+a^2+b^2] ==
a(b^3-1)}]
which returns (on version 8.0, and also version 9.0)
{{b -> -(a/(1 + a))}, ...
- asked by Ashley Montanaro (8 votes), answered by gpap (2 votes)
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Greatest hits from previous weeks:
==================================
[Finding the centroid of the area between two
curves]\url{http://mathematica.stackexchange.com/questions/17170/finding-th
e-centroid-of-the-area-between-two-curves}
When I have an area bounded by curves, is there a built-in way to find
the center of the area? Or do I have to plot it first and then use
ComponentMeasurements on it?
For example: the area under $y= ...
- asked by a3f (9 votes), answered by george2079 (3 votes)
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[How can I improve Mathematica's resolution on a macbook retina
display?]\url{http://mathematica.stackexchange.com/questions/18419/how-can-
i-improve-mathematicas-resolution-on-a-macbook-retina-display}
Mathematica looks a bit fuzzy on the retina screen, how can I increase
the resolution?
Here another screenshot showing a direct comparison between the browser
and Mathematica
- asked by Tom Wellington (23 votes), answered by programming_historian
(10 votes)
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Can you answer these?
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[Setting PropertyValue for VertexWeight is not
persistent]\url{http://mathematica.stackexchange.com/questions/32320/settin
g-propertyvalue-for-vertexweight-is-not-persistent}
g = CompleteGraph[8, VertexSize -> Medium];
PropertyValue[{g, VertexList[g][[1]]}, VertexWeight] = 10;
PropertyValue[g, VertexWeight]
{10, 1, 1, 1, 1, 1, 1, 1}
PropertyValue[{g, ...
- asked by Ilya Sorokin (2 votes)
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[Orthogonal basis of a hermitian
matrix]\url{http://mathematica.stackexchange.com/questions/32350/orthogonal
-basis-of-a-hermitian-matrix}
Is there a way to extract an orthogonal basis for a hermitian matrix in
Mathematica?
A simple diagnolization returns a non orthogonal basis and later using a
Grahm-Schmidt process which isn't aware ...
- asked by user9522 (1 vote)
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[Convert ImageSize to
FieldSize]\url{http://mathematica.stackexchange.com/questions/32459/convert
-imagesize-to-fieldsize}
How might I construct a function called EmToPX[p] such that the
following 2 InputFields would be the same width. If not please explain
why doing such isn't possible.
InputField["a", ImageSize -> ...
- asked by Liam William (1 vote)