# All Questions

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### 2D vector treatment and visualisation

I'm just trying to define a set of vectors, in the Cartesian plane, draw the vectors originating from the origin $O,$ and be able to add vectors and draw the resulting vector. I've started doing ...
71 views

### How to animate a graph generated by ListPlot command point by point?

I was wondering if it is possible to animate the following graph. The command used to generate the graph is the following: ...
51 views

### WhenEvent behavior changed from v9 to v10 - how to fix the code?

A couple of years ago I asked a question about solving n-body systems with NDSolve and detecting collisions with WhenEvent. I ...
85 views

### Using a table as a variable in a function

I have a bunch of arrays and need to extract specific rows and columns of these that obey certain criteria. So for one table I'd do like this ...
77 views

### Plot Multibeam bathymetry grid

I don't speak Mathematica very well, but I am sure I could do great things with this programming language! I will delete this question if it is a duplicate, but I will be glad if you could point me ...
35 views

### Read raw data from ipad accelerometer and gyro in real time [closed]

I need some strategy to have real-time access to raw data of IPAD (or Iphone) accelerometer and gyro. Any hint to start?
13 views

### check the equivalent [duplicate]

Let f:=x^3+xyz+z^3; Let mat={{2,2,2}, {3, 1, 7}, {1, 6, 3}, {4, 5, 1}, {0,4, 9}}; I want to check at which point of m that the first derivate at x = the first derivate at y = the first derivate at z ...
48 views

### Discrete Fourier Transformation

Assuming I have a function $f(x)$. I can use a numerical Fourier transformation: NFourierTransform[] to find some points of $F(\omega)$. How can I do the same ...
60 views

### How to solve this non-linear equation? [closed]

b=12 a=2.787 solve[b/x-((1-(a*(((b x)/(b+2 x))^(4/3))))^(-2/3))- ((1+(a*(((b x)/(b+2 x))^(4/3))))^(-2/3))==0,x] I gave the above code and the output came ...
38 views

### Apply Grad and Mod to Matrix

Let f:=x^3+y*x*z+z^3; Let mat = {{2, 2, 2}, {3, 1, 7}, {1, 6, 3},{4, 5, 1},{0,4,9}}; be a list of points . I want to compute ...
44 views

### what is the relation between a circle and a triangle? [closed]

A triangle has three angles,and pi is made of three angles. What are the relation between pi and a triangle?ex:$\pi$÷$180×60×3=\pi$
51 views

### Import graphml file in mathematica

I am trying import a graphml file I created with NodeXL in mathematica in order to create a network. However when i try to import it I get the error message: "Cannot import data as GraphML format". ...
29 views

### Option ItemAspectRatio in GraphicsGrid has weird behaviour in MMA 10.3

Has anybody noticed that the Option ItemAspectRatio in GraphicsGrid is no longer valid? It ...
46 views

### Solve a system of first order ODEs with variable coefficients

I am totally new to Mathematica, so sorry if my question could seem stupid. I'm trying to solve this system of ODEs \begin{align*} &S'(a)=-\lambda(a)S(a)+{\tau}R(a)\\ ...
42 views

### Mathematica cannot find intersection of two functions [closed]

Why mathematica cannot solve this extremely easy equation? [![My functions][1]][1] g[x_] := -x + 2 h[x_] := 3 x f[x_] := -x^2 + 4 http: // ...
100 views

### How to create a series using For loop.? [on hold]

i want to create a series such as 10^n-1 * 10^n-2 *.......... * 10^2 * 10^1 using for loop ; here is my code. For[n=1, n<18, a=10^n; n++, b=(10^n)*a;]; ...
16 views

### Edit header information of a DICOM file and export it again

I have some DICOM files and want to edit a part of the Header and export the DICOM files with this edited header. I know how to Import a DICOM files and extract the Header Information, but how to ...
33 views

### Please explain this pattern/Message related issue and help with finding workaround

I attempted to clean up my code and also add messages to functions if they are called with wrong arguments. This introduced some error which I tracked down to the following: ...
116 views

### Filter a specific area of an image

I try to obtain the angle of the periodic waves that you can see below. I am using the FourierTransformation to get it: ...
51 views

### How to put the result of NDSolve in a function?

I have solved an ODE with NDSolve, and put the result in S: S = NDSolve[{y'[x]==(y[x]^4+y[x]+1)^(1/2),y[0]==0}, y, {x, 0, 100}] But i don't want to plot y[x] ...
40 views

### NDSolve with piecewise function gives error “Encountered non-numerical value for a derivative at x == 0.” [duplicate]

I am solving differential equation with piecewise function and i am getting error that NDSolve::ndnum: Encountered non-numerical value for a derivative at x == 0.. ...
143 views

### How to plot heatmap function over the unit circle

I have a function $Z(r, \theta)$ that I would like to plot over the unit disk. I could of course plot it as $Z(\sqrt{x^2+y^2}, \arctan(y/x))$, but the best I can do with this is a square plot. I would ...
71 views

### How to created visualization dashboard for summary data?

I would like to create the following dashboard: The numbers indicate my desired dimensions for the cells. I would like the cells to contain a regional plot, a trend line, and bar charts. I have ...
56 views

### How to do literal replacement to format expression?

I can do a replacement of an expression with some variables to alternate symbols: ...
295 views

### Create a Pascal Matrix

I am trying to write a function that can create a Pascal matrix. So far I have ...
26 views

### How to get a Basis set BS from a polynomial set PS in Wu's Method [closed]

Here are three polynomials , I want to get a basis BS from them in Wu's Method ,moreover ,for more polynomials ,how can I get it? ...
29 views

### Re-ordering a nested list according to second element [closed]

I am dealing with very large lists, but to illustrate my problem consider the following list: ...
60 views

### inset legend from top right corner / find size of swatchlegend bounding box

The question is the following. Using Inset, we can insert a legend in a Plot (in a Graphic, in general). E.g. ...
59 views

### Defining special function or variable for a derivative in mathematica

I have a question in Mathematica, I would appreciate it if you possibly answered me. What can I do for defining a special variable for derivative of arbitrary variable. For example, imagine I have a ...
36 views

### Scaling the output of TemporalData object

The RandomFunction generates an output in the form of TemporalData. How can I plot a scaled version of this data, e.g., all values divided by $n$ with time kept fixed? I read this post but couldn't ...
82 views

### How do I solve a system of equations for only one variable quickly?

I have four order-2 polynomial equations in four unknowns. Call the unknowns x1,x2,x3,...
53 views

### Difficulty achieving the desired output configuration [closed]

In order to describe the associated issues please see code sample below. The code presented is a simplified to include only whats needed as to better communicate the problems at hand. Following code ...
104 views

### Alignment of TreePlot

I want to construct a binomial tree using TreePlot but have troubles with the alignment. The code ...
50 views

### How to derive finite-difference scheme automatically on a quite general stencil

Info This question is a generalization of the following one Derivation of numerical scheme for linear transport equation on a variable stencil. Statement of a problem Linear scalar hyperbolic ...
31 views

### Second order differential equation, with term from previous numerical solution

I have a second order differential equation, in terms of a term that was previously obtained from numerically solving another equation. Numerical solution of equation before 2nd order equation: ...
102 views

### Comparison between numerical solution of nonlinear ode and nonlinear ode of second order

Background Let's consider the following initial value problem for nonlinear system $$\begin{cases} E' &=& 1 - n_e, \\ n_e' &=& -8\,n_e\,E, \end{cases} \tag{1}$$ with the following ...
43 views

### Evaluation of InverseFunction at the boundaries of its domain

Folks, I want to numerically evaluate a InverseFunction h[x] close to the edges x5 and ...
63 views

### How to fix internal error “too much recursion” when trying to compute a definite integral

I'm completely new to Mathematica. I got a 14 day free trial and I'm using the online version. I'm trying to use it to check the results of an integration I performed by hand. But I'm not getting any ...
48 views

### How to get the values out of Alternatitves?

Saying we have something like: SomeFunction[ ... { Alternatives[1, 2, 3] :> "something" } ... ] How can I know if ...
45 views

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### finding invertible matrix $g$ such that $gAg^{-1}=B$ [closed]

So I have two matrices $A$ and $B$ with dimensions $78\times78$. Is there any way to find such a $g$? I tried rewriting as $Bg-gA=0$ and using ...
91 views

### Replicate an image from Documentation Center (EulerMatrix)

EDIT I try to produce an image similar to that (see here) but this time with an ellipsoid. I hope I am not wrong but the code that creates this beautiful image is not available in Mathematica's ...
46 views

### Is it possible to somehow parallelize PadeApproximant in Mathematica?

Is it possible to somehow parallelize PadeApproximant in Mathematica? I'm dealing with a too long function (including exponential and trigonometric terms) in ...
183 views

### Getting $e$ closer than $0,001$?

Everyone knows that $\sum \frac{1}{n!} =e$. How should I make a program in Wolfram Mathematica, that tells me, how many members I need from the sum, to get a number, with mistake smaller, than ...
75 views

### Mathematica suspends long calculation [on hold]

I have the following weird problem: I am performing some monte carlo simulations through a simple do loop, where each round takes about 1-5 minutes. I was running 1000 or so overnight, and realized ...
61 views

### Function where variable is integration bound

Lets say I have a function of the form: $f(T) = T^4 \int_0^{1/T} \frac{x^3 dx}{e^x-1}$ This is an example of the situation I am describing not a unique problem. I want to define it as a numerical ...