8.13 October 1, 2013
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Top new questions this week:
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[Compiling ColorFunction for faster complex phase-amplitude
plots]\url{http://mathematica.stackexchange.com/questions/32977/compiling-c
olorfunction-for-faster-complex-phase-amplitude-plots}
I have gotten into the habit of plotting complex-valued functions on a
plane using a color-function along the lines of
Function[{z}, Hue[Arg[z]/(2 Pi), 1, Abs[z]]].
For example, the following code ...
- asked by user93655 (16 votes), answered by halirutan (15 votes)
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[Pattern to match L, but not
L[_]]\url{http://mathematica.stackexchange.com/questions/33025/pattern-to-m
atch-l-but-not-l}
I have an expression where I want to replace L but not L[_]
For example, the following doesn't work and
sub = {L :> 2};
L + L[tilde] /. sub
(* 2 + 2[tilde], but I want 2 + L[tilde]*)
Is there ...
- asked by jlperla (13 votes), answered by Szabolcs (20 votes)
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[Is there a Mathematica barcode
reader?]\url{http://mathematica.stackexchange.com/questions/33093/is-there-
a-mathematica-barcode-reader}
Is there a Mathematica barcode image reader (much like TextRecognize)
that allows the user to enter an image of a barcode and then read it to
get an output string?
- asked by David G. Stork (12 votes), answered by belisarius (13 votes)
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[How to enlarge $\it{Mathematica}$'s knowledge about certain
functions?]\url{http://mathematica.stackexchange.com/questions/33251/how-to
-enlarge-itmathematicas-knowledge-about-certain-functions}
I'm often troubled with the following task. I need to carry out
symbolical computations involving certain special functions. Let me take
as an example Barnes gamma-function. It is included in ...
- asked by Weather Report (9 votes), answered by WalkingRandomly (6
votes)
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[Labeling a three-dimensional
plot]\url{http://mathematica.stackexchange.com/questions/33236/labeling-a-t
hree-dimensional-plot}
As the title says, I want to add some text in a three-dimensional plot,
thus labeling specific parts of it. Here is the corresponding
Mathematica code
V = 1/2*(x^2 + y^2 + z^2) + (x^2*y^2 + x^2*z^2 + ...
- asked by Vaggelis_Z (7 votes), answered by Kuba (7 votes)
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[Mathematica: computing a difficult
integral]\url{http://mathematica.stackexchange.com/questions/33217/mathemat
ica-computing-a-difficult-integral}
I am trying to compute the following integral:
Integrate[Exp[Sum[-((cw*\[Lambda] - b[i])^2/(2*\[Sigma]^2)), {i, 1, n}]], {cw, 0, 1}]
And currently Mathematica outputs
(Sqrt[\[Pi]/2]\[Sigma](Erf[(Sqrt[n](\[Lambda]-
- asked by emaster70 (7 votes), answered by ybeltukov (8 votes)
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[How to always display current section identifier (number, name) in
notebook?]\url{http://mathematica.stackexchange.com/questions/33173/how-to-
always-display-current-section-identifier-number-name-in-notebook}
Because I find myself relocating frequently within a long notebook
divided into sections, subsections, & subsubsections, I would like
to display the identifying information for the section, etc. ...
- asked by Brandon Marshall (7 votes), answered by ybeltukov (4 votes)
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Greatest hits from previous weeks:
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[Plotting Complex Quantity
Functions]\url{http://mathematica.stackexchange.com/questions/3458/plotting
-complex-quantity-functions}
Trying to plot with complex quantities seems not to work properly in
what I want to accomplish. I would like to know if there is a general
rule/way of plotting when you have complex counterparts in ...
- asked by night owl (8 votes), answered by Artes (12 votes)
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[How can I extract data points from a black and white
image?]\url{http://mathematica.stackexchange.com/questions/3831/how-can-i-e
xtract-data-points-from-a-black-and-white-image}
Consider the following graph (source):
Is there any way to extract the data points from this image in a
semi-automatic way? I have seen, and tried the methods suggested in this
question, but they ...
- asked by Eli Lansey (29 votes), answered by Sjoerd C. de Vries (33
votes)
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Can you answer these?
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[How to embed graphic-element-specific metadata within a Graphics
object?]\url{http://mathematica.stackexchange.com/questions/33207/how-to-em
bed-graphic-element-specific-metadata-within-a-graphics-object}
One of the most crucial requirements for rich, interactive scientific
graphics is being able to "annotate" individual graphic elements (e.g.
the data points of a scatterplot, the individual curves in ...
- asked by kjo (1 vote)
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[How to compute the Lovasz number for the given graph in
Mathematica?]\url{http://mathematica.stackexchange.com/questions/33010/how-
to-compute-the-lovasz-number-for-the-given-graph-in-mathematica}
Here is a graph whose adjacency matrix is
m = {
{0, 0, 0, 0, 0, 1, 1, 1, 1, 1, 0, 0},
{0, 0, 0, 1, 0, 0, 1, 1, 1, 0, 1, 0},
{0, 0, 0, 0, 1, 0, 1, 1, 1, 0, 0, 1},
{0, 1, 0, 0, 0, 0, 0, 1, 0, 1, 1, ...
- asked by Eden Harder (3 votes)
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[NDSolve error when solving
pde]\url{http://mathematica.stackexchange.com/questions/33166/ndsolve-error
-when-solving-pde}
I am trying to calculate speed of viscous fluid in a rotating hollow
sphere. The sphere is rotating round z axis. The fluid is
incompressible. I used Navier-Stockes equations. The only boundry ...
- asked by Jure (1 vote)
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New blog post:
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[Plotting electronic orbitals using
Mathematica]\url{http://mathematica.blogoverflow.com/2013/09/plotting-elect
ronic-orbitals-using-mathematica/} by Jason B on Sep 27