6.36 Tuesday, April 28, 2015

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Top new questions this week: 
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[Removing a histogram’s vertical edges]http://mathematica.stackexchange.com/questions/80949/removing-a-histograms-vertical-edges

Let’s say I have a histogram:

Histogram[RandomVariate[NormalDistribution[10, 2], 500]]

How can I remove vertical lines inside the histogram and keep only the edge?

- asked by moso (18 votes), answered by halirutan (12 votes)

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[Generating animations of clouds with Mathematica]http://mathematica.stackexchange.com/questions/80486/generating-animations-of-clouds-with-mathematica

I’d like to generate some visually-pleasing animations of clouds, fog or smoke with Mathematica. My idea of "visually-pleasing" is along the lines of one of the images on the Wikipedia article for ...

- asked by blochwave (17 votes), answered by Simon Woods (18 votes)

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[Better way to visualize cylinder puzzle solution]http://mathematica.stackexchange.com/questions/80902/better-way-to-visualize-cylinder-puzzle-solution

The above puzzle has been a recent source of amusement in my clique.

I decided to provide a visualization to motivate solution (here):

My code:

s[x_] := Piecewise[{{4 Mod[x, 3]/3, 
     ...

- asked by ubpdqn (13 votes), answered by Jens (21 votes)

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[Mathematica 10.1.0.0 (OS X) high CPU usage even for empty notebook]http://mathematica.stackexchange.com/questions/80630/mathematica-10-1-0-0-os-x-high-cpu-usage-even-for-empty-notebook

Since update to 10.1.0.0 Mathematica has a high CPU usage even when no evaluation is running (even for empty notebook opened). I am running OS X Yosemite 10.10.3 on the following configuration:

...

- asked by Honza Drchal (11 votes), answered by BlBl (0 votes)

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[Right Ascension and Declination in astronomical functions] http://mathematica.stackexchange.com/questions/80787/right-ascension-and-declination-in-astronomical-functions

In the process of answering this question, I was forced to confront the various astronomical coordinate systems used by Mathematica.

Background

In astronomy, positions of celestial objects (stars, ...

- asked by Virgil (10 votes), answered by Virgil (12 votes)

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[Can’t inject EncryptedObject] http://mathematica.stackexchange.com/questions/80763/cant-inject-encryptedobject

Here are minimal examples:

encryptedObj = Encrypt["pass", "TestCase"]; 
 
Decrypt["pass", encryptedObj] (*returns correct "TestCase"*) 
 
 
 
With[{x = encryptedObj}, Button["Try with", Decrypt["pass",  ...

- asked by Kuba (10 votes), answered by WReach (7 votes)

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[Difference between Fitting Algorithms] http://mathematica.stackexchange.com/questions/80998/difference-between-fitting-algorithms

I am new to Mathematica, and I don’t quite understand, what the difference between the fitting algorithms Fit, FindFit, LinearModelFit, NonLinearModelFit are. Why is the syntax so different (\(1,x,x^2\) ...

- asked by Luca Thiede (9 votes), answered by MarcoB (10 votes)

================================== Greatest hits from previous weeks: ==================================

[How to make Jacobian automatically in Mathematica] http://mathematica.stackexchange.com/questions/5790/how-to-make-jacobian-automatically-in-mathematica

If we have two vectors, a and b, how can I make Jacobian matrix automatically in Mathematica?

$$ a=\left( 
\begin{array}{c} 
 \text{x1}^3+2\text{x2}^2 \\ 
 3\text{x1}^4+7\text{x2} 
\end{array} 
$$

- asked by George Mills (19 votes), answered by Jens (26 votes)

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[Is there an open source implementation of Mathematica-the-language?] http://mathematica.stackexchange.com/questions/4454/is-there-an-open-source-implementation-of-mathematica-the-language

I’ve seen questions before such as "What is the best open-source equivalent for Mathematica?", but that specific question (and that line of inquiry in general) cares more about the computer algebra ...

- asked by sblom (59 votes), answered by Simon (50 votes)

================================== Can you answer these? ==================================

[Easy FindMaximum returns a wrong answer] http://mathematica.stackexchange.com/questions/81065/easy-findmaximum-returns-a-wrong-answer

FindMaximum in region is a new function in mma10,but when I tried the following example:

region = Polygon[{{0, 0}, {10, 0}, {10, 5}, {5, 5}, {5, 10}, {0, 10}}] 
FindMaximum[{x + y, {x, y} \[Element]  ...

- asked by WateSoyan (2 votes)

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[Diverging solution to coupled second order ODEs from NDSolve] http://mathematica.stackexchange.com/questions/80692/diverging-solution-to-coupled-second-order-odes-from-ndsolve

For a physics application I am considering the radial Bogoliubov-de Gennes equations in two dimensions. In dimensionless form they read as follows

$$ 
\begin{cases} 
 ...

- asked by Funzies (3 votes)

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[Does "FiniteRingData" or something like that exists?] http://mathematica.stackexchange.com/questions/81009/does-finiteringdata-or-something-like-that-exists

I want to find a function like FiniteGroupData but for finite rings. Does something like that exists?

- asked by kp9r4d (1 vote)