6.35 Tuesday, May 5, 2015

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Top new questions this week: 
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[Two, maybe related, issues with ParallelTable] http://mathematica.stackexchange.com/questions/82496/two-maybe-related-issues-with-paralleltable

I will use a very simple example for demonstrating two issues I face with ParallelTable, one with respect to the speed and one with respect to the use of memory. These issues might be related.

Let us ...

- asked by Fred Simons (14 votes), answered by Mr.Wizard (2 votes)

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[Switch from logarithmic to linear scaling partway along a plot’s axis] http://mathematica.stackexchange.com/questions/82581/switch-from-logarithmic-to-linear-scaling-partway-along-a-plots-axis

In the 2015 Planck satellite results, they give the latest plot of the temperature power spectrum of the cosmic microwave background, which I show below. (I am only interested in the main plot; you ...

- asked by thecommexokid (11 votes), answered by LLlAMnYP (13 votes)

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[Solving and Animating Three Body Problem] http://mathematica.stackexchange.com/questions/81340/solving-and-animating-three-body-problem

I am attempting to solve a three-body problem using the Lagrange formalism, with a 1/r potential.

I started off by defining T and U (kinetic and potential energy) as follows:

Tx = .5 m1  x1'[t]^2 +  ...

- asked by Puru (11 votes), answered by Vitaliy Kaurov (22 votes)

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[Analyze touching particles with holes in a microscopic image] http://mathematica.stackexchange.com/questions/81176/analyze-touching-particles-with-holes-in-a-microscopic-image

I am looking for an easy method to count individual particles in a microscopic image. It is quite difficult for Mathematica to detect them, because they are touching each other. I am quite a beginner ...

- asked by Niki (11 votes), answered by nikie (15 votes)

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[How do I draw a polygon defined by a list of data points?] http://mathematica.stackexchange.com/questions/81191/how-do-i-draw-a-polygon-defined-by-a-list-of-data-points

I am attempting to make a 3D model of a device defined by a list of x,y,z points, digitized from a 2D image. The z coordinate is defined in mma.

What I tried so far:

area = 0, 452.45658, ...

- asked by Peter (10 votes), answered by kguler (7 votes)

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[Is there a good reason for the removal of this FrameTicks syntax?] http://mathematica.stackexchange.com/questions/82625/is-there-a-good-reason-for-the-removal-of-this-frameticks-syntax

In past versions of Mathematica one could use a terse syntax for FrameTicks:

bottom, left, top, right

In 10.1 this syntax is no longer recognized requiring the addition of two sets of brackets:

...

- asked by Mr.Wizard (8 votes)

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[How to remove outliers from data] http://mathematica.stackexchange.com/questions/81121/how-to-remove-outliers-from-data

I have a data with noise which some times includes significant outliers. The position of the outliers are random.

For example:

data1 = Table[PDF[NormalDistribution[3.5, .8], i], i, -5, 15, .01] + ...

- asked by Algohi (8 votes), answered by lalmei (8 votes)

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

[1 Plot, 2 Scale/Axis] http://mathematica.stackexchange.com/questions/627/1-plot-2-scale-axis

I would like to plot those two datasets on top of each other. But they have very different range on the \(y\) axis. How can I have two different axis?

I found the following on the help menu but quite ...

- asked by 500 (81 votes), answered by ArgentoSapiens (75 votes)

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[How to find the position of elements in a list satisfying criteria] http://mathematica.stackexchange.com/questions/180/how-to-find-the-position-of-elements-in-a-list-satisfying-criteria

Say I have a list x=2,4,6,8,10 and I want to find out the positions of the elements that are greater than 7.

Select[x, #>7&] gives the elements themselves, and Position[x,8] gives the  ...

- asked by PeterR (24 votes), answered by Guess who it is. (19 votes)

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

[Arrowhead becomes unattached to line in a Graphics3D Manipulate]http://mathematica.stackexchange.com/questions/81306/arrowhead-becomes-unattached-to-line-in-a-graphics3d-manipulate

I’m trying to Manipulate a Graphics3D figure, and am seeing some errors. If I execute the following code, and move the slider, the head on one of arrows bounces around, unattached to the line of the ...

- asked by rhomboidRhipper (2 votes)

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[How to define \(\operatorname {Mc}\) and \(\operatorname {Ms}\) Mathieu functions in terms of MathieuC and MathieuS?] http://mathematica.stackexchange.com/questions/81395/how-to-define-operatornamemc-and-operatornamems-mathieu-functions-in-t

Reading multiple books about Mathieu functions, I always come across notation like \(\operatorname {ce}_r(z,q)\), \(\operatorname {se}_r(z,q)\) for angular functions and \(\operatorname {Ce}_r(z,q)\), ...

- asked by Ruslan (2 votes)

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[Partial Differential Formatting by default] http://mathematica.stackexchange.com/questions/82629/partial-differential-formatting-by-default

I read

http://blog.wolfram.com/2011/12/15/mathematica-qa-series-converting-to-conventional-mathematical-typesetting/

and I could use pdConv mentioned there, or

pdConv[f_] :=  TraditionalForm[ f  ...

- asked by Hojin Cho (1 vote)