8
votes
2answers
70 views

How to use `Except[]` inside of `Pick[]` [duplicate]

Pick[{1, 2}, {0, 1}, Except[0]] returns {1, 2}, the first element of which I did expect to be excluded. What is the thing I ...
8
votes
1answer
101 views

How can I use Mathematica to make a captcha image?

This was inspired by this post which is about the serious business of website deployment in the Wolfram Cloud, and interaction with Google's reCaptcha system. I started thinking of how to make those ...
0
votes
1answer
48 views

How to find this probability with PDF from TransformedDistribution?

I need to find the expression for the following equation, where $m>0$ ...
1
vote
1answer
63 views

Inconsistent Integrate behavior?

Evaluating the following integral with Mathematica Integrate[q0/(-1 + q0^2), {q0, 0, A}] gives a conditional expression ...
2
votes
0answers
54 views

Interface design to replace cascading dialogs which don't work

I would like to make a nice Interface of a simulation I wrote, but i don't know how. I want that you run the code and then a window asking for input of some values appears (either in the same ...
9
votes
6answers
548 views
5
votes
1answer
45 views

How to understand the different output of two UnsetShared?

Update From technical support, Thank you for contacting Wolfram Technical Support. I understand that you are reporting an issue with UnsetShared deleting the shared variable after a second ...
2
votes
2answers
53 views

How to translate/convert UTF-16 code to its corresponding word/characters by Mathematica?

I'm using Mathematica10.0.2 on my Win7. Recently I crawled some websites by mathematica and within the information returned by URLFetch there are plenty of UTF-16M codes. These UTF-16M codes are ...
5
votes
2answers
148 views

NSolve behaving differently in V9, V10.3 and V10.4

EDIT In a very fast response from Wolfram they state that this is a known problem and give an example of it working for version 10.4.1. $Version "10.4.1 for Microsoft Windows (64-bit) (April ...
0
votes
2answers
61 views

Random 3D cylinders plot [duplicate]

I have seen this trivial example for circles ...
-1
votes
0answers
74 views

Integral Equation Solving [on hold]

I need to solve two coupled equations such as ...
0
votes
0answers
65 views

NMinimize vs Simulated Annealing [on hold]

Update I would find the global minima, the plotting shows that this function has many local minima. ...
0
votes
0answers
41 views

How to obtain the PDF of variable that is square of a Rician distributed variable? [on hold]

If a random variable $X$ is Rician distributed with PDF $f_X(x)$ where $$f_X(x)=\frac{2x}{\alpha}\text{exp}\left(\frac{-(x^2+v^2)}{\alpha}\right)I_0\left(\frac{2xv}{\alpha}\right)$$ Then what is ...
0
votes
0answers
29 views

Reduce expressions modulo quadratic monomials more efficiently?

I need to evaluate a function of the matrix $\begin{pmatrix}A & B\\ C&D\end{pmatrix}$ and arbitrary odd primes $p$ and $q$. Moreover, I need to set all non-linear terms in the $A,B,C$ and $D$ ...
1
vote
1answer
52 views

Graph not plotting any points [closed]

f [x_] := (x + ln[x] - 3) Plot[f[x], {x, 0, 5}] How come this comes out with an empty graph? I tried this and same results: ...
2
votes
1answer
29 views

Exporting String to NetCDF

I've already read a Q&A stating that because NetCDF does not support primitive string type variables, that it is impossible to export a string to a NetCDF file. For example: ...
3
votes
0answers
34 views

Constraining Function to be positive with NDSolve, Allee effect

I am trying to numerically solve the steady-state behaviour of the Allee effect (with one spatial dimension, diffusion): $\frac{\partial n}{\partial t} = D \frac{\partial^2 n }{\partial x^2} + ...
0
votes
0answers
27 views

Take a derivative of a NIntegrate function (with two argument) [on hold]

what I have is a numerical function of SBE[m,T] and I want its derivative with respect to T. Here is what I wrote, ...
2
votes
0answers
41 views

KernelObject appears dead problem [on hold]

my cluster got 24 cores And I use this setting to do parallel computing ...
2
votes
0answers
87 views

What is a good way to model fluid stream contours around airfoils?

I am an undergraduate student and am doing a project on conformal mapping for my complex analysis class. I have had one heck of a time trying to plot stream function contours to model fluid flow in ...
6
votes
1answer
76 views

Wolfram Cloud and reCAPTCHA

Is there a piece of Wolfram Language code out there that integrates reCAPTCHA (for human verification) into the Wolfram Cloud environment? This is what the reCaptcha service looks like (in Swedish): ...
-1
votes
1answer
47 views

How to run code and do data analysis in mathematica [closed]

I am a beginner in Mathematica. I'd like to do something like the following: write code- ouput- write code- output... But when I created my own notebook and copy the code above, I don't know how to ...
0
votes
2answers
125 views

The Disc and Washer Methods [on hold]

How is it possible to demonstrate a visual solid of revolution utilizing the washer method? For example to show the shape formed by rotating the region bounded by $y=(x-2)^4, 8x-y=16$ about $x=10$? ...
-5
votes
0answers
35 views

System of partial differential equations using Mathematica [on hold]

As you can I am trying to solve a system of partial differential equation using MATHEMATICA. However, I could not. Can anyone provide me with a code which is able to solve such equations in ...
3
votes
0answers
73 views

Kernel crashes when computing finite difference mixed derivative with respect to y & z but works fine when computing with respect to x & y or x & z?

I am using Mathematica 10.4.0 on Ubuntu 16.04. I am trying to solve a set of differential equations using finite difference method on an NxNxN cubic grid (x, y, z directions). I am getting a weird ...
5
votes
1answer
71 views

Finding the correct boundary conditions to a specific problem

I want to reproduce the following problem in the figure: $$\phi''+c\phi'\sqrt{m^2\phi^2+\phi'^2}+m^2\phi=0$$ where $\phi=\phi(x)$ with $x \in (-\infty,\infty)$, $c=\sqrt{3/2} \ $ and $m=0.2$. ...
0
votes
0answers
37 views

How dangerous is 'Overflow occurred in computation' message? [on hold]

I got this warning at the end of rather lengthy symbolic calculation. The result seems feasible, but I am interested, whether this problem may bight be later, so to say. Thanks=)
3
votes
2answers
89 views

Switching Differential Equation in NDSolve

I am trying to solve the following system of differential equations using NDSolve: $\dot{z}_t=.5(1-z_t)$ $\dot{y}_t=.05y_t+z_t-x_t$ subject to the following constraint: $-y_t-z_t\le0$ where $z_t$ ...
6
votes
1answer
109 views

Left Right Straight Maze

How do I generate a Left, Right and Straight ordering for a maze for something like the following? Similar to generating a left and right ordering for someone walking in real life. ...
4
votes
2answers
202 views

Calculate $\pi$ using Monte Carlo methods

I know that we can have an estimate of $\pi$ using Monte Carlo methods. I know that we make a huge loop and each time we take randomly two numbers in the range [0,1] and calculate the number of ...
0
votes
0answers
38 views

Construct certain univariate functions over bounded interval having given set of moments [migrated]

We have a class of probability distributions (parameterized by $\alpha =\frac{1}{2},1,\frac{3}{2},2,\ldots$) over the interval $[-2^{-12} \cdot 3^{-3},2^{-16}]$ having as their $n$-th moments ...
0
votes
2answers
84 views

I'm trying to solve a system of complex equations

I'm simply trying to solve a system of equations and mathematica can't do it for all values over the region of interest. I have a 3x3 matrix that has a specific parametrization and after squaring the ...
1
vote
1answer
75 views

Use Map on a Function with two variables

I am new to Mathematica and I would like to find out how to use Map on a function with two parameters such as: ...
1
vote
2answers
94 views

NSolve won't act on very large powers

I noticed that NSolve isn't running properly when I have some seemingly harmless numbers in my expression. Here is a simple example: ...
2
votes
2answers
56 views

Substituting within a function definition that includes Simplify

I would like to define a function like myfunc[f_] := Simplify[(f/g)] where g will be substituted/replaced with the current value of g at the time of definition. ...
3
votes
1answer
35 views

Show In/Out names in some notebooks but not others?

I often have a working notebook and a "publication notebook". Figures and results are copied to the publication notebook to which explanatory text is added. The publication notebook can then be saved ...
1
vote
2answers
53 views

Scale in plot and Piecewise

I wrote this code: ...
3
votes
1answer
66 views

Checking if input is a function

I would like to write a program to find the leading coefficient of a given polynomial. (Sounds easy, right?) I'd like to be able to handle the format x^2-x+7 (with ...
4
votes
3answers
252 views

Enforce monotonicity in a list

Suppose I have a list containing pairs of complex numbers. For example: ...
3
votes
2answers
88 views

RegionPlot with LogScale

I would like to have my RegionPlot with logarithmic scale in x and y. My code looks like ...
3
votes
3answers
166 views

Return a sentence with numerical values

I have the following function: example[a_, b_] := Module[{c}, c = a + b; Return["The solution is c"] ] I would like to know how to return that ...
0
votes
2answers
66 views

FindInstance function

I have a question concerning the FindInstance function. If I write FindInstance[c == 3, {c, l}] I obtain {{c -> 3, l -> 33/10 + (8 I)/5}} Is there any ...
6
votes
2answers
72 views

Annoying behavior of a dynamic angular gauge

I want to do something that can be simplified into the following toy example: I want to dynamically show the count down to a future date on an AngularGage. The ...
3
votes
0answers
46 views

JournalArticle does not react on the PointSize option

The Default StyleSheet recognizes the PointSize option for ListPlot: ...
3
votes
1answer
67 views

Problem with ComponentMeasurements and property “Centroid” [closed]

I am showing here three test images to investigate the output of ComponentMeasurements when using the property "Centroid". ...
2
votes
1answer
70 views

issue with Animate

I want to make a animation based on the dataset like data = Flatten[Table[{x, y, x^2 - y^2}, {x, -3, 3}, {y, -3, 3}], 1]; I show this data using a ListPlot3D. ...
0
votes
0answers
59 views
2
votes
0answers
43 views

The correct assignment of probability distribution to generate random variables

I'm asking you for a help to solve a difficult (for myself) task. Now I will tell you what and why I'm trying to implement. The task is to simulate the passage of elementary particles through a ...
4
votes
0answers
42 views

Spell checking in German texts - strange behavior

This questions is about spell checking in German within Mathematica. I have encountered some strange behaviour of Mathematica's spell-checker. Words within the dictionary are sometimes marked as ...
1
vote
1answer
65 views

How to improve the smoothness of ContourPlot3D at the boundary

I want to ContourPlot3D[] a iso-surface. $3$ independent variable are α1, α2, Ψ, respectively. The codes are as follows (the ...

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