12
votes
1answer
167 views

Global` context not empty at startup in v10.2.0

Bug introduced in 10.2 and persisting through 10.2 or later Note that the analysis of this problem revealed a different problem than in Potential pollution of Global` context in fresh kernel (see ...
6
votes
2answers
148 views

Number of divisors visualized with the QPochhammer function, how improve performance of code?

I have this code that is originally Jeffrey Stopple's code for the Riemann zeta function in the complex plane. Because I discovered yesterday that the number of divisors can be generated with the ...
0
votes
0answers
20 views

Custom drop-down list of tags for Dataset Keys similar to CountryData

CountryData produces a drop-down list of tags when you enter a string. I would like to replicate this functionality for a ...
15
votes
3answers
357 views
+100

Returning multiple results from a LibraryLink function

What is the best way to return multiple inhomogeneous results from a LibraryLink function? Imagine that the result of a single computation is several tensors of different dimensions and several ...
11
votes
0answers
185 views

Possible bug with FourierTransform linearity

Each component is easily transformed but the sum is not: FourierTransform[f''[x], x, k] FourierTransform[f'[x], x, k] ...
1
vote
1answer
79 views

How to find a cycle with a property in a graph

Let's have a graph with this edge list: edgelist = {s -> 1, s -> 2, 1 -> 3, 2 -> 1, 2 -> 4, 3 -> 2, 3 -> t, 4 -> 3, 4 -> t}; I want ...
3
votes
3answers
478 views

Efficiently compute double sum

Is there a "Mathematica Way", like Map or Apply to compute the following double sum? $\sum_{i=1}^{N_1}\sum_{j=1}^{N_2} m_i n_j \, f(\tau_{i} \gamma_{j})$ I have already stored the lists ...
1
vote
2answers
83 views

How to get the desired (equivalent) answer from Integrate?

This is the integrand: 1/beta/(2*z)/(1 - beta) // TraditionalForm Integrating with respect to z, gives ...
13
votes
2answers
575 views

Where is the “Function Navigator” and “Virtual Book” gone?

Under V9 "Help" was a Item each for "Function Navigator" and "Virtual Book" to find and one could work with it. Under V10 these Helpers are gone. Although under Documentation/English/System the ...
3
votes
4answers
197 views

Trouble with Position[] [duplicate]

I am in trouble with Position, Although my example works as expected it throws a warning. Position[{{a,b},{a,c},{a,b}}, _?(#[[2]]==b&), {1}] During ...
5
votes
2answers
122 views
+50

What's the difference between Interpolation[pts, Method -> Spline] and BSplineCurve?

Last month, I answered a question about spline interpolation,please see here Now I do the following operations ...
12
votes
2answers
348 views

Interpolation on a regular square grid spanning a triangular domain

Bug introduced in 10.0 and fixed in 10.1 Context I am trying to identify contours of a function which is sampled on a cartesian grid within an irregular (triangular) region. Here is the data ...
4
votes
1answer
68 views

upper limit with `PlotStyle` in `GeoListPlot` in v10.1

Bug introduced in 10.0 and fixed in 10.2 Let's start with the code below: ...
0
votes
2answers
39 views

“Part specification is longer than depth” warning in Position function [duplicate]

I'm working on a project which analyzes financial data. I download the price and dividend information for the SPY ETF which tracks the S&P 500: ...
8
votes
2answers
137 views

Difficulty using LUDecomposition

I'm having trouble using LUDecomposition with pivoting. I read the Mathematica help on this particular command, but I'm still lost. Take a matrix like: ...
0
votes
0answers
61 views

JacobiCN inaccuracy [on hold]

For my calculations I need JacobiCN[s,k] for s near 0 from the left and k near 1 from the ...
1
vote
1answer
58 views

Same scale for all the axes in Plot3D

I can't find this in the documentation. How do you force the same scale for all the axes when making a 3D plot? There is the BoxRatios option, but this only changes ...
29
votes
2answers
2k views

Playing with Matrix falling code in Mathematica

I was trying to create a Matrix falling code image with Mathematica. Here is my code: ...
0
votes
1answer
350 views

Mathematica Implementation of Householder’s Method

I typed the Householder code in this paper, which starts on page 7. The code is: ...
5
votes
1answer
601 views

How to implement Kemeny-Young method? (rank aggregation problem)

Prehistory I am trying to make some statistical analysis of some experimental data, arises from measurements made ​​on an ordinal scale. I faced with the problem of rank aggregation: to get from ...
0
votes
0answers
147 views

step by step interactive indefinite integral

WolframAlpha can give step by step solution for indefinite integral. There seems to be similar question but for derivatives. Is there a way that I can generate my own step by step solution for ...
3
votes
3answers
251 views

3D Gamma function

I try to plot the following function: Plot3D[Gamma[1+0.5*(n+m)]/Sqrt[Gamma[1+n]*Gamma[1+m]],{n,0,1000},{m,0,1000}] I expect that for m=n and near to it the value ...
8
votes
1answer
161 views

How to change the font color of a variable in whole input cell

I want to track the occurrence of a particular variable in a code. So the idea is to change its color. Usually I do it in a crude way - convert the code into text and then use ...
0
votes
0answers
43 views

Solving matrix optimization

I have the following problem. Let $X_1, X_2, \cdots, X_k$ are $n \times n$ Hermitian matrices (need not be positive) given. Let a $n \times n$ positive matrix $A$ is given such that $Tr(A.X_j)<0$ ...
28
votes
1answer
950 views

Fast Spherical Harmonics radiative transfer

This is a rather specific question and I apologize for spamming you with some lengthy code. But it could be interesting for some reader and maybe you can help out, so please bear with me. I am using ...
7
votes
2answers
168 views

Why is mathematica eating a row from QRDecompostion

I'm attempting to calculate the QRDecomposition of the matrix: a= {{1,3},{0,5},{2,-8}} QRDecomposition [a] The answer mathematica gives me is: - Q which is a ...
0
votes
0answers
57 views

Mathematica requirements management [on hold]

Is there a way to use Mathematica notebook as a requirements document as it's possible in IBM DOORS ? ...
8
votes
3answers
304 views

Redefining a built-in operator

Is there a way I can redefine the || operator such that a||b will be 1/(1/a + 1/b)? Is it ...
2
votes
1answer
134 views

How to write 1.0 in InputFields with ContinuousAction and Number constraint

With the concept of user responsiveness in mind, I’ve tinkered a couple of small apps that are supposed to be eh… responsive, i.e. calculating without having to press enter. They all rely on ...
0
votes
1answer
39 views

Why can not the vector be transposed in integrating over a region? [duplicate]

Clear[x, A]; A = {{2, -1, 0}, {-1, 2, -1}, {0, -1, 1}}; Integrate[Exp[-x.A.{x}\[Transpose]/2], x \[Element] FullRegion[3]] This code raises an error ...
1
vote
1answer
63 views

Simplifying Expressions for FindMinimum

I am currently trying to apply the FindMinimum function to find the lowest energy of an expression. My current expression as of now is relatively complicated. It is the summation of 48 similar terms, ...
16
votes
1answer
513 views

How to add named characters to Mathematica 10?

It appears that native support for the Klingon alphabet has been removed from version 10: \[KlingonA] Syntax::tsntxi: "\"!(\[ KlingonA])\" is incomplete; ...
2
votes
1answer
69 views

Clean & efficient bounding box non-intersection test

I would like a quick test to tell me that segments $ab$ and $cd$ cannot intersect in the plane. If the maximum $x$-coordinate of $a$ and $b$ is less than the minimum $x$-coordinate of $c$ and $d$, ...
2
votes
0answers
19 views

Page breaks and headings in long table or grid

I have a need for long tables in a document I am producing but I am having difficulty. The printed document ends up with page breaks midway through the table which cuts rows part way through. I'd also ...
7
votes
1answer
169 views

How to make sure polygon is drawn flat in 3D?

Bug introduced in 8.0 or earlier and persisting through 10.2 or later I'm working on this SE question about pentagrams on top of dodecahedron for exercising. Both solutions are basically connecting ...
-3
votes
0answers
59 views

I want a mix matrix [on hold]

I have a matrix with dimensions m x n and elements f[p, q] and another matrix with dimensions i x j and elements g[r, s]. How ...
0
votes
0answers
52 views

How to simulate a homogeneous nucleation? [on hold]

From this topic, Animating a Voronoi Diagram, I can simulate heterogeneous nucleation. Based on Voronoi diagrams, how can I use Mathematica to simulate homogeneous nucleation?
0
votes
0answers
44 views

How to get an element mesh from a region?

I've been exploring a new 3D solid commonly called the "Chestahedron" (7 faces of equal area). I wanted to find the centroid, so turned to Mathematica and found it!:) Other things of interest turned ...
3
votes
1answer
89 views

Equality of Reciprocal with Negative Exponent

I want MMA to tell me if two, rather large, expressions are equal. My minimum working example follows. I want MMA to tell me that the following is true:$$x^n = \left(\frac{1}{x}\right)^{-n}$$ I have ...
5
votes
2answers
107 views

Generating and Imaging of the water molecules with Graphics3D [duplicate]

my problem is I don't know how to generate e.g. 20 water molecules: Graphics3D[ Rotate[First@ChemicalData["Water", "MoleculePlot"], 45 Degree, {8, .5, 0}]] ...
5
votes
3answers
99 views

ImplicitRegion gives arbitrary boundaries

This question uses Mathematica 10.2.0.0. equation1 is the major unbounded region I would like to generate: ...
13
votes
1answer
155 views

FullSimplify wrongly reduces expression to zero

Bug introduced in 9.0 and persisting through 10.2 or later I get the following output with a fresh Mathematica (ver 10.0.2.0 on Mac) session ...
6
votes
2answers
216 views

How to simplify only the lowest level of a nested expression [on hold]

I have a large expression that takes forever to simplify if I apply FullSimplify[...]. The expression has lots and lots of brackets that luckily already groups ...
3
votes
1answer
61 views

How should I iteratively refine a MixtureDistribution?

I am trying to find a stopping time for a randomized simulation such that say 95% of trials that will be successful will have already finished. I would like to do this by creating and then refining ...
10
votes
4answers
382 views

Mathematica complaints that convergent integral diverges

Bug introduced in 10.0 and fixed in 10.0.2 Trying to do the integral ...
7
votes
1answer
251 views

Problem with Neumann condition in quarter disc

Bug introduced in 10.0 and fixed in 10.2 So I'm following the available examples in version 10 for FEM, The plane stress operator is shown as this ...
19
votes
2answers
579 views

Why is TextString[-0.5] a positive number?

Bug introduced in 10.0 and fixed in 10.0.2 I want to format numbers in decimal notation and chose TextString for this task. But today, when looking at the final ...
0
votes
0answers
36 views

Once working code fails upon restarting Mathematica [on hold]

I had a code which worked flawlessly, then upon shutting down mathematica and re-starting it, the code failed with the following error message: "The function value -Abs[f[0.0228659,I/6]] is not a ...
0
votes
0answers
32 views

choosing the number of points in FindFit function [on hold]

I am trying to find the best function to fit a set of data as following, ...

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