0
votes
0answers
8 views

solve for x in the following equation. Assume that a,b,c,d,f,g are constants. (ax+b)(cx+d)=(cx+f)(ax+g)

solve for x in the following equation. Assume that a,b,c,d,f,g are constants. (ax+b)(cx+d)=(cx+f)(ax+g)
0
votes
0answers
7 views

seach combinaisons of terms that equals a sum within a sequencial ordered linear values? [on hold]

subset size k = 2 (can be > 2) Sum to find = 11 sequence : 1,2,3,4,5,6,7,8,9,10.. n => result of k-size [1,11] [2,9] [3,7] ....
1
vote
1answer
13 views

BarLegend problem when rescaling color of multiple vectorplot

I want to rescale colors of multiple vector plot. Similar posts are (1), (2) I made a minimal example to show the problem I encountered ...
0
votes
1answer
27 views

Missing curves in a plot

I am trying to plot multiple curves for a particular parameter in a function S1, where the only variable is t and the rest are ...
0
votes
0answers
29 views

Conjugate[A/B+C/D]

Trying to obtain the result of Conjugate[A/B+C/D] only gives the same result. As such, I use Refine as: ...
0
votes
0answers
33 views

The function I defined is not giving any output [on hold]

Could anyone tell me why the function I have defined is not giving any output? When I run it, gen is not showing any output. Thanks! ...
2
votes
3answers
97 views

Plot independent 2D graphs on walls of 3D Plot

Sorry, I know a lot of similar questions have been asked before, but I just can't find one that exactly describes my problem. How can I make the according 2D (marginal distribution) graphs appear on ...
1
vote
2answers
50 views

FindRoot with Grad

I want to find a numeric solution using Grad. With Solve, I get ...
4
votes
1answer
55 views

getWSLINK documentation vs reality

The example in the documentation for getWSLINK says WSLINK link = libData->getWSLINK(libData); Compiling ...
1
vote
0answers
30 views

Compute second functional derivative with VariationalD?

I have problems to compute the second functional derivative of a general function. The following lines generate the first derivative: ...
0
votes
0answers
32 views

Can MMA solve this min-max optimization problem symbolically?

I have a nonlinear optimization problem with linear constraints. How to solve this? $\sigma_i$ and $\rho_i$ are the optimization variables. $\min\hspace{1mm}\max{D_1,D_2}$ subject to ...
3
votes
0answers
51 views

Wrong limit: Limit[(1 + (-1)^n/n)^n, n -> Infinity]=1 (Mathematica 10.4 and W-Alpha)

Since $(1-\frac{1}{n})^n\to 1/e$ and $(1+1/n)^n\to e$, the sequence $(1+\frac{(-1)^n}{n})^n$ has no limit as $n\to\infty$, but has limits for odds and even numbers. If $n$ were taken to be real, there ...
4
votes
1answer
52 views

3DPlot Rendering Artefacts (z-fighting)

I am trying to render a matrix as a depth map: ...
1
vote
0answers
29 views

Wave equation PDE with changing boundary condition

This is my first post here, normally with mathematica I will solve out the PDE using eigen function expansion or separation of variables and then model the solution in mathematica. However this time I ...
0
votes
1answer
55 views

Mapping over function's several parameters regions

About this post: Mapping multiple parameters of a function to specific values I wonder if the parameters a and b have ranges ...
0
votes
1answer
49 views

Wrong numerical results from LegendreP

{Cos[Pi/180] // N, LegendreP[46, 0.9998476951563913`], LegendreP[46, Cos[Pi/180]] // N} give ...
6
votes
1answer
166 views

Vastly incorrect answers obtained by increasing WorkingPrecision with modified Bessel functions

This is a follow-up to this question regarding numerical instabilities occurring with modified Bessel functions. In trying to explore J.M.'s answer to that question in greater depth by setting ...
1
vote
1answer
33 views

REAL Roots of a 2 variable Polynomial

I am looking to plot the real zeros of polynomials of two variables in Mathematica, but I have encountered an issue. To accomplish this task I have been using ContourPlot to plot the polynonial ...
0
votes
1answer
54 views

Optimization of the solution to an ODE

Apologies if this is obvious -- I'm very new to Mathematica. I'm trying to minimize the solution to an ODE with respect to a variable. The following code generates the solution to the ODE, ...
0
votes
0answers
22 views

Eigenvalues of a symbolic matrix using interpolating function

I have a 6x6 matrix with entries that depend on dependent and independent variables of an interpolating function. I would like to be able to evaluate the eigenvalues of this matrix using the ...
1
vote
2answers
56 views

Modeling Gaussian Distribution for 4 Variables

I have 4 random variables A,B,C,D, that all have the same variance $\sigma^2$, but they are independent of each other. What I am trying to find, or to at least approximate, is the standard deviation ...
1
vote
2answers
73 views

How to plot a lattice (2D or 3D) given a basis

I want a graphical picture of a lattice with basis such as $\{(1,1), (\sqrt{2}, -\sqrt{2})\}$. Does Mathematica already have a pre-made function that finds all linear combinations over $\mathbb{Z}$ ...
0
votes
2answers
55 views

DensityPlot with logarithmic xy-axes and logarithmic color scale

I would like to do a DensityPlot with logarithmic xy-axes and logarithmic color scale for the function \begin{align} S(\epsilon_{v},\epsilon_{\phi}) = \frac{\pi}{\epsilon_{v}} \frac{\sinh ...
0
votes
0answers
56 views
0
votes
0answers
50 views

Minimize: which algorithm is in use?

How can I know which algorithm has been used by Minimize to solve a given problem? Can I force Minimize to use a specific ...
0
votes
0answers
51 views

Tricky inverse Laplace transform

I'm trying to compute the inverse Laplace transform of $f(s) = s^c/(N + s^{ir} )$ where $c,N \in \mathbb{C}$ and $r \in \mathbb{R}^+$ using the Bromwich integral $$ F(t) = \frac{1}{2 \pi i} \int_{- ...
0
votes
0answers
30 views

sample size for classify

I was wondering how many pictures the classify function can process. It seems as soon as several hundred pictures are used for training the program freezes. Picture measurements are 1482x849 pixel and ...
2
votes
2answers
65 views

How to extract coordinates {x,y,z} from Raster3D

I want to extract coordinates out of a Raster3D. It is possible to extract coordinates out of an Image3D by using ...
9
votes
1answer
99 views

Visualisation of the field of algebraic numbers in the complex plane

Hot to plot the field of algebraic numbers in the complex plane? In this picture, the color of a point indicates the degree of the polynomial of which it’s a root: red = rational numbers ...
0
votes
1answer
50 views

Solving for Polynomial roots

This simple Solve gives the roots of a quadratic: Solve[a x^2 + b x + c == 0, x] However, if I factor the polynomial in terms ...
0
votes
2answers
28 views

Finding vertices with a given degree; or, finding indices

I have a graph g and would like to find all the vertices in g with degree n. ...
1
vote
0answers
41 views

Map over multidimensional matrix

Suppose I have a 8by6by4by2by2 matrix called m. There is in total 8*6*4 2by2 matrices. I want to map a function over these 2by2 matrices. Each dimension in ...
-2
votes
0answers
28 views

How to solve nonlinear system of four PDE

DSolve[{D[Subscript[g, 11][u, v, t], t] == -2 [Psi][u, v, t] Subscript[L, 11][u, v, t], D[Subscript[g, 22][u, v, t], t] == -2 [Psi][u, v, t] Subscript[L, 22][u, v, t], D[Subscript[L, ...
1
vote
1answer
33 views

Color in Spherical3DPlot according to value

I want to colour a 3D plot according to it's value. I could only mange in one direction (say in 'z' direction) but I want to show them in all direction together. I have written the following code: ...
2
votes
1answer
24 views

What is the default `SignificanceTest` setting for `FindClusters` with `Optimize` method?

According to the documentation, the default value of FindCluster's Method option is ...
0
votes
0answers
32 views

Interval arithmetics and complex numbers

I am trying to do some simple calculations for a computer assisted proof and since they are not too demanding I thought of using Mathematica. I seems that Mathematica is great for interval ...
2
votes
1answer
34 views

An issue evaluating RegionInteresect

Description: I am trying to find a RegionIntersect between a Disk and a Polygon. I have ...
0
votes
0answers
41 views

How to apply a function to a list, being able to use a list index inside of the function? [on hold]

In the documentaion I find things like: M = {a, b, c}; kappa[x_, y_, z_] := x PauliMatrix[1] + y PauliMatrix[2] + z PauliMatrix[3] kappa @@ M // MatrixForm But ...
2
votes
3answers
351 views

Animated point following a sinusoidal path on sphere

Could someone help me with animating a point following a $\sin$-like path on the sphere? It should be something like this: This green point should walking on a sine (this red line) around sphere.
4
votes
1answer
121 views

How can one match a function in a replacement rule

I'm trying to write a delayed replacement rule that is capable of matching both the functions and their parameters, like ...
0
votes
1answer
44 views

ColorFunction causing division by zero error (going outside domain?)

On the following plot example, I get a division by zero error (10.4.1): ...
0
votes
0answers
42 views

Can parallelization speed up FindClusters?

I have a clustering task that would take FindClusters 2-3 months1 to complete. Can this calculation be sped up with parallelization? (FWIW, the data to be ...
0
votes
0answers
3 views

Double Integral Range [migrated]

we want the Surface between the two equation: $r= 1 + cos\theta$ $r = 1$ (circle) we can use a duble integral to solve this: $$ S = \int_{-\pi/2}^{\pi/2} \int_1^{1+cos\theta} r \,dr\,d\theta $$ ...
1
vote
1answer
53 views

How to label individual points in data set with use of SciDraw?

I'm trying to lable each point in data set and adjust corresponding TickLabels. Here is my code: ...
-1
votes
0answers
47 views

Code conforming to math in Java/Sage code

I've already posted a question here asking for help writing code. Here's the key points: I'm looking for a way to use calculate OEIS A144311 efficiently in Mathematica. This series considers ...
0
votes
0answers
54 views

Equation cannot be solved with the methods available to Solve [duplicate]

I am a beginner to Mathematica. I am trying to get the solution of such equation as: Solve[-b*M + L*R - a*M*Log10[L*c + (L*d*(1 - M)*S)/R] == 0, R] Constants are ...
1
vote
0answers
37 views

finding list by expresion

Well Im new to mathematica. I have list of x which contain {1,23,45,6,43}. And I get expression from g = Fit[t, {1, v, v^2}, v] how can apply list x to g to ...
9
votes
1answer
87 views

How to correctly implement in a new function the scoping behavior of Table, Sum and other commands that use Block to localize iterators?

It is documented that "Block is automatically used to localize values of iterators in iteration constructs such as Do, Sum, and Table." Therefore the dummy index (iterator) in a Sum is shielded ...
2
votes
1answer
41 views

zooming out and adding text to revolutionplot3D

I am trying to work some details for to the following animation: ...
0
votes
0answers
49 views

Definite and indefinite integral give different results

I'm trying to find an expression that, given $x$, $y$, and $R$, gives the indefinite 2D integral of a function at the circle centered on $(x_0, y_0)$ with radius $R$. With $g$ as defined below, I'd ...

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