# All Questions

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### Input equation to find Fixed Point

I have the following equation: Subscript[x, n+1]=Subscript[x, n]^2+c with Subscript[x, 0]=0. this equation is restricted to R and c is Real. How do I input this into Mathematica to find the fixed ...
8 views

### How to transform abstract finite group to permutation group?

It seems that mma only has group function for permute group? Then there is a step to transform the abstract finite one to permute one. As an example, consider the following problem Suppose ...
9 views

### errors STL export, contains rotate or GeometricTransformation

I failed to export a STL file containing a Graphics3D with a Rotate or GeometricTransformation. ...
41 views

### Using Java log4j in Mathematica

Someone has a code example of how log4j can be used to create logs in Mathematica? RLink uses it, as can be checked in ...
22 views

### Streamplot in one direction

R gives explicitly the seeding points and I want the stream lines to be drawn in one direction only, outside the circle ...
29 views

### Lyapunov exponent of a Henon map?

Can anyone help me with calculating Lyapunov exponent of 2D map, for example Henon map? If there is simple code, that would be great!
26 views

### “Reduce” works fine for a non-linear system with 9 equations, but cannot solve it if 10 equations. Any ways to improve the code?

I am trying to solve a class of problems, which are basically about a solution to a system of non-linear equations subject to the constraint that some subset of solutions must be non-decreasing. I ...
62 views

Why does this work: Graphics[{Circle[{0, 0}, -Pi/4]}] But this doesn't? Graphics[{Circle[{0, 0}, N[-Pi/4]]}] Telling me: ...
29 views

### Plotting a parameterized vector in the x-y plane

I am trying to plot the trajectory of a parachutist descending at a constant vertical rate of 8 m/s while a south wind also blows at a rate of 8 m/s. He initially jumps from a height of 300 m. I am ...
37 views

### Comparing unit normal definition in calculus with FrenetSerretSystem

I'm trying to compare the unit normal definition in calculus texts (i.e., $\vec N=\vec T'/||\vec T'||$) where $\vec T$ is the unit tangent vector, with the unit normal vector returned by the ...
61 views

### DSolve documention on web differs greatly from distributed MMA 10.2.0 version

In the course of improving my answer to 95361, I noticed that the DSolve documentation on the web is much better written than that distributed with Mathematica ...
112 views

### Generate multiple integer variables with constant sum

I have asked similar question three day ago[The old question]. it was incorrectly marked as duplicated. This time I make this question more general and closer to reality. I want to build a model of N ...
39 views

### Lloyd relaxation on VoronoiMesh

How can we apply Lloyd's relaxation algorithm to a VoronoiMesh? Thanks. UPDATE Thanks a lot KennyColnago for your answer. Based on Simon Woods sugestion of using ...
111 views

### Trying to model a chemical reaction - NDSolve::litarg error

I am trying to model a chemical reaction with NDSolve. I have specified the known differential equations and parameters, ...
50 views

### Purchasing a laptop to fit Mathematica system requirements [on hold]

I need to buy a new laptop and I intend to run the latest student edition of Mathematica (I am not sure if that is equivalent to Mathematica 10). What I don't understand are the specifications needed ...
68 views

### Plot Text Data in Mathematica

I am trying to analyze some text data for my thesis! How can I plot this data in Mathematica in a barplot based on the frequency of the words and combinations of them? On the Abscissa (...
45 views

### A bug in Rasterize?

I plot a straight diagonal line and then simply rasterize it. Consider what happens (Mathematica 10.2 on Windows 7 x64): ...
54 views

### How can I illustrate the solution space of these equations in 3D?

I would like to plot the solution space $\{\theta,\varphi,\Omega\}$ of this vector equation, \begin{pmatrix} \sin (\theta ) \sin (\varphi ) \sin (2 \pi \Omega )-\sin (2 \theta ) \cos (\varphi ) ...
98 views

### PixelValues along a straight Line

UPDATE to the question I have reformulated the question in order to make it distinct from the one suggested as a duplicate: "Line Intensity Profile From Image." The key difference is that I'm ...
38 views

### Program for fractional-order Lorenz system

Here, I am writing the Mathematica program for fractional-order Lorenz system by using Euler method. Please check the following code and correct it. Program: ...
23 views

### Solve the maximum point of B-spline basis when its mathematical expression is unknown

Description Let $\vec{U}=\{u_0,u_1,\ldots,u_m\}$ denotes a non-decreasing sequence of real numbers, i.e, $u_i\leq u_{i+1} \quad i=0,1,2\ldots m-1$. and the $i$-th B-spline basis function of ...
27 views

### Filling option failing when used with ListLogLinearPlot

As mentioned in this question the following filling seems to work well. ...
15 views

### Using Solution of NSolve when Passing a Function Inside [on hold]

I apologize if any of my questions are super easy, I am new to Mathematica. If I do something like this: f[x_] := 1/2 (3 x - x^3) a = NSolve[f == x, x] I will ...
39 views

### Solve 4 equations using Solve [on hold]

I'm trying to solve $4$ systems of equations with $4$ unknowns. There are some trig involved and I keep getting error "Solve::ifun: inverse functions are being used by Solve." Please help me to ...
39 views

### HoldForm -> InputForm without processing the contents

I have programmatically generated a large number of simple equations like 1+1/2. I need them to be 'unprocessed', so they've been run through ...
34 views

### Why do notebooks reset themselves now and then? [on hold]

Now and then I am working on a notebook and suddenly it reset itself. What I mean is that I am entering commands and when I type enter, the notebook command number goes to 1 and I have lost all ...
35 views

### Fourth derivative of a Bessel function [migrated]

I am given with a relation $$\frac{d^2}{dx^2}(P_l(x))=\frac{1}{2}\sum_{n=(0,1),2}^{l-2}(l-n)(l+n+1)(2n+1)P_n(x).$$ Using the above equation, I get ...
75 views

### Newton's Method Converges in Mathematica for non-convergent functions

In mathematica I set f[x_] := Sign[x] Sqrt[Abs[x]] and then I solved it in a root finding for Newton's method by doing ...
32 views

### ListPlot3D and plotting a 3 dimensional array [on hold]

I have a 3D array of the form: {{{a1,a2,a3},{b1,b2,b3}...}}} and ListPlot3D only accepts data of form: ...
56 views

### Correlation suspiciously high [on hold]

I used the Correlation function and got a value that seemed suspiciously high. The two series look like this when plotted: Correlation[fri1E, fri2E] // N ...
28 views

### How can i interpret these Clayton copula (parameter 0.723) graph in hydrology? [on hold]

PDF, CDF and Contour plot please explain these three graphs...........
71 views

### Find subsequence A in sequence B A007908 - OEIS

I have sequence A as A007908 - OEIS and pattern B which is a sub-sequence of that sequence A. I need to find index of first occurrence of the given pattern. For example pattern ..1010... I've looked ...
59 views

### Turning table into association for Classify

I have the following sample data for 20 users. I know their sex, and the response for three yes/no questions. I am trying to building a classifier to guess their response to the third question, based ...
85 views

### Inverse of parametrized ellipse area

If you parametrize an ellipse (with the center, not a focus, at the origin) as: {a Cos[t], b Sin[t]} the area traced out from the focus (not origin) for a given ...
65 views

### Can I map a function over a sequence of arguments without making the arguments into a list first?

I would like to set evenFunction[f_][a_, b_, c_, ...] = f[Abs[a], Abs[b], Abs[c], ...] I have come up with two ways to do this so far. Use pure functions ...
81 views

### DSolve gives an empty solution set to a solvable ODE

I really hope this isn't a duplicate, today I was answering this question and was to lazy to solve the quadratic equation on my own and so just asked mathematica to give me the solution of the ...
38 views

### Fail to Create a package [on hold]

This is rather basic. In an empty notebook I type in a single cell ...
41 views

### Call an executable

I have one data file, one executable file and one *.txt with the results from running the executable, all within the same folder. The folder has the path C : \ Users \ Dimitris \ Desktop \C32EXE ...
29 views

### How to prevent space trimming when importing HTML with ImportString?

I am importing a HTML-formatted string with ImportString[string, "HTML"] to properly parse all HTML-escaped characters like ...
154 views

### Consecutive identical integer members of a list

Can you help me to find and count sub-sequences of consecutive, identical integer members of a long list (at least 1000 members)? By sub-sequences I mean runs like ...
25 views

### Launch Front End from .NET MathKernel and return result to .NET

Is it possible to launch a front end and open a notebook from a .NETLink kernel and return a result from the notebook to .NET? In the code below "x" appears in the .NET textbox after 10 seconds but ...
168 views

### A tricky algebraic simplification

This code produces a complicated output: ...
46 views

### Ctrl + Shift + 6 produces some weird symbol instead of power

I'm trying to configure the Ctrl+^ shortcut to produce Superscript instead of Power as described here, but for some reason I ...
51 views

### Mathematica computes too slowly at the start of a session [on hold]

Everyone, I'm a Mathematica new user. I find it a problem that, when I start a new Mathematica session, it executes too slowly for the first command (say, "1+1", it may take a few seconds before it ...
240 views

### Plotting a Bifurcation diagram

I have the following system equation v'(t)=2*G*J1[v(t-τ)]cos(w*τ)-v(t) How do you plot the bifurcation diagram, τ in the x ...
432 views

### Defining indefinitely many functions

Is it possible to define a class of indefinitely many functions f1, f2, f3, ... such that ...
40 views

### How to generate a Log BarLegend for a DensityHistogram

I have a Log count histogram: DensityHistogram[myData, 100, {"Log", "Count"}, ColorFunction -> "Rainbow", ChartLegends -> Automatic] But ...
49 views

### Factoring out a common term

Very simple question, but I can't find a simple answer here or in the documentation. I have an expression: qq = a x + b x^2 + c x^3 and wish to factor out a ...
New to the site and Mathematica. I'm trying to use the finite element method to get a temperature profile. So if $q_0=f(T_0,T_1)$, $q_n=f(T_{n-1},T_n)$ and we also know that ...