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3 votes
1 answer
52 views

Approximating exponential generating function (EGF) from values of generating function (OGF)

I have a function that can evaluate ordinary generating function, and need to construct an approximation to the exponential generating function by using a few calls to the ordinary generating function....
0 votes
0 answers
53 views

On a formula in Wolfram|Alpha [migrated]

I need to understand a formula for the Hypergeometric function $_3F_2(a,b,c;d,e;1)$ I searched and got the following from Wolfram alpha ( see:- second formula in https://functions.wolfram.com/...
  • 97
0 votes
1 answer
70 views

Dsolve to find vector potential component's

I want to find the vector potential component's. I expand the Poisson’s equation in cylindrical coordinates which yields the three equations as in the picture. The equation along rho direction equal ...
  • 1
3 votes
3 answers
112 views

Plot the graph of an integral

If I have a system of differential equations, I solve it and save the result in Sol: ...
  • 33
2 votes
1 answer
145 views

Analytical Solution in Generalized Heat Equation

Given the following problem $$u_{t}-\frac{v}{2}\cdot u_{xx}+\frac{v}{2}\cdot x^2 \cdot u(x)=0 $$ $$u(x,0)=f(x)$$ Where $ f(x)=y_1(x)+0.2y_4(x)+0.01y_6 (x) $ $y_n$ are the Eigenfunctions that defined ...
5 votes
2 answers
152 views

Sorting a list by a single particular element in a specified order

I have a list of lists -- a list of sublists -- that I wish to sort in a specified order. The following function, sortBy2ndElement, sorts a list of lists (...
  • 9,747
2 votes
4 answers
404 views

How can I properly plot this region, with some filling too?

I have to plot this region: $$A = \{(x, y)\in [0, 2]\times [0, 1]; x+y \leq 2\}$$ Here is what I did: ...
  • 217
3 votes
0 answers
73 views

Compiling a function that uses MapThread

I'm looking for tips on quickly applying the following update to $B$ pairs of $(w_i,x_i)$ $$\text{step}(w_i,x_i)=w_i-a x_i \langle w_i, x_i \rangle$$ Below is a readable but very slow version ...
2 votes
4 answers
95 views

Splitting list into sublists based off string value [duplicate]

I'm new to Mathematica so please bare with me! I wish to split an imported data list off of {x,y} values based off the y value, and then sum the corresponding parts. An example of the imported list: <...
  • 153
0 votes
2 answers
62 views

One-way "cross" of function between two matrices

I'm trying to create a sort of one way "cross" of a function between two matrices, such that every pair in one matrix is mapped to every pair in the other, but not the other way around; for ...
  • 101
1 vote
0 answers
32 views

Hold around SetDelayed with Graphics [duplicate]

Minimum Working Example I've defined my own plot function, which does a lot of stuff to the inputs before passing it into the Graphics function. Because of that, I'...
0 votes
0 answers
39 views

Non-minimal coupling ξ , Minkowski false vacuum decay case (shooting method) (An update to the previous question)

I asked a few days ago this question: Non-minimal coupling ξ - numerical bounce solutions (shooting method, false vacuum decay) Alex Trounev helped me improve my code building based on this paper (...
0 votes
0 answers
18 views

Unknown Cell Collapse Type

Going through a notebook someone else put together, there are segments where a cell is mostly collapsed - you can see it is a code cell but not the code inside, but you can still evaluate the cell (...
  • 105
5 votes
2 answers
86 views

Bug of ChoiceDialog

I am using Mathematica 13.1 on Windows 11. I have the following bug with ChoiceDialog: ...
  • 5,112
0 votes
0 answers
23 views

Building the documentation index in the cloud

How do I generate a persistent documentation search index in the Wolfram Cloud? Unlike in a local Mathematica installation, the ...
  • 1
0 votes
0 answers
35 views

Tracing the phases (i.e. the minima) of a potential

Is there a Mathematica package to trace the minima of a potential as a function of some parameter, returning its phase structure? Working with particle physics models (in the context of cosmology and ...
3 votes
4 answers
152 views

Cannot Draw a Composite Piecewise Function

I have defined two functions: g, which is a piecewise function, and h, which is the composition of g. ...
3 votes
1 answer
43 views

DSolve output displays different from actual output after using locator in Manipulate

V 13.2.1 on windows 10 If you look at this it does look bizzar, right? The same variable sol is different from what it should be above it. But the above ONLY ...
  • 127k
0 votes
0 answers
34 views

Retrieving the documentation search ranking in Mathematica

I want to write a function that takes a search term and returns a list of built-in symbol suggestions. The add-on function DocumentationSearch`SearchDocumentation ...
  • 1
0 votes
1 answer
47 views

The shortcuts for typing subscript is valid

I installed the Mathematica 13.2 in my new computer, everything worked well excepted that the shortcuts for typing the subscripts "ctrl+ _" doesn't work. I tested that the "ctrl" ...
  • 129
3 votes
3 answers
224 views

Intersection points of two-variable polynomials

Let $h$ and $g$ designate two multivariable polynomials: $$\!\!h(x,y)=-96\! \left(32 x^2\!+\!8 x (3\!-\!8 y)\!+\!40 y^2-28 y+5\right) \left(10 x^2+x (4 y-2)+\quad\quad\quad\\ \quad\quad+(1-2 y)^2\...
  • 159
2 votes
0 answers
34 views

Using "ToNumberField" as opposed to equations over the integers

Let D>1 be a square-free rational integer, and write \Q for the rationals. I am trying to determine the (non-)membership of ...
  • 121
0 votes
0 answers
45 views

How to solve a fourth-order coupled system?

I would like to solve the following differential equations by NDSolve Constants ...
  • 117
0 votes
0 answers
54 views

The error estimates of the implicit Euler method in the book have different results [duplicate]

I use DSolve and NDSolve to solve a set of differential equations respectively, where NDSolve specifies an implicit Euler method, and subtract the results of both solutions to obtain the truncation ...
0 votes
1 answer
81 views

How to start another notebook calculation when one notebook is running?

If your first notebook is running and needs a long time to finish, but you still need Mathematica to do other calculation in another notebook. The second notebook will not start until the first ...
  • 65
5 votes
1 answer
207 views

Inaccuracy for FEM for 3D Heat Equation

I'm simulating the heat transfer within a cylindrical rod, with external heating from its sides. ...
  • 103
0 votes
1 answer
58 views

Trajectories Missing From Phase Plane

I am attempting to graph trajectories for the system of equations (with independent variable t) given by x'=5x-3y-2 y'=4x-3y-1 in the phase plane. For some reason, I can only graph trajectories for ...
  • 5,211
3 votes
1 answer
40 views

Strange output of NIntegrate when constraining the precision with $Pre

One can constrain the precision of NIntegrate by setting PrecisionGoal: ...
  • 2,754
2 votes
1 answer
52 views

Moment problem for a discrete probability distribution

Is there an elegant way to use Mathematica to find entries of a discrete probability distribution $\{p_i\}$ by using a finite number of calls to $m(t)=\sum_i p_i^t$? There's a wikipedia article on ...
0 votes
0 answers
34 views

How to zoom, pan and otherwise visualize a huge graph?

I have a complicated tree I'd like to zoom in and investigate. It's quite dense and large. Here's a simple way to reproduce the problem (my graph has 30K elements) but the 1K elements of this graph ...
  • 2,369
1 vote
1 answer
59 views

Extract complex lists

I ask for the first time here. I am not good at English , so I don't know that whether I can well tell you my question. I want to create a model in which insects carry pollen from plants. First, I ...
  • 11
3 votes
1 answer
137 views

On the solution of systems equations with exact coefficients

It all starts with the following system of equations that I can't solve by hand: ...
  • 4,402
1 vote
1 answer
47 views

Plot with manipulate

I want to use appropriately use the Manipulate command in conjunction with Plot, to construct animated graphics for the evolution of the solution. I have tried but i could not succed to solve it $f(x)=...
3 votes
2 answers
100 views

Update Random Each Repetition of Animate

I found a solution that's not what I wanted but it will suffice Thanks - Larry ...
2 votes
2 answers
82 views

Place frame in the correct position

I am plotting different waves (computed numerically and analytically) and, for that, I have used the following code: ...
  • 21
4 votes
1 answer
96 views

How to find the common eigenvectors of these commuting matrices?

Given matrices P and Q defined as P = {{x - I y, z}, {z, x + I y}}; Q = {{0, 1}, {1, 0}}; ...
  • 387
2 votes
0 answers
39 views

DSolve bvlim error due to Boundary condition

I am solving an Ode using Mathematica: $$-p\alpha x^{p-1}=m\ddot{x},\quad x(0)=x_0,\quad x'(0)=x''(0)=0,\quad x(t_1)=0.$$ And I have $p\alpha>0$, all $x$ and $t$ are positive. I want to figure out $...
  • 31
2 votes
1 answer
75 views

Background color depending on external function value on the same plot

I would like to plot a two dimensional list (ListPLot [{x, y[x]}]) where the background color is changing with x value according to the value assumend by an external function f[x]. Thank you. Sorry, I ...
5 votes
1 answer
110 views

Mesh `Cylinder[{{0,0,0},{0,0,1}},1]` with inner boundary `x=y=0`

In a meshed cylinder Cylinder[{{0,0,0},{0,0,1}},1] I need to specify DirichletConditions along ...
0 votes
0 answers
42 views

Statistics Clarification [closed]

I'm learning pretty basic statistical concepts, and want to clarify that my understanding is correct. I created a drawing to visualize what I think is correct, and I need to know if this is right or ...
5 votes
1 answer
100 views

Minimizing computational time for a quantum walk problem

Any suggestions as to how to speed up the computational time for this quantum walk problem which is coded using a normalized SparseArray coin operator as follows: ...
  • 3,128
0 votes
3 answers
108 views

Plotting Average Positions of 2D Random Walk

I need to generate a plot that shows the averaged position at n steps of 1000 different random walks that are each 1000 steps long. So far I am using ...
1 vote
0 answers
50 views

ContourPlot fails to plot a simple triginometric function squared [closed]

The two plots should be exactly the same in the following. However, the one squared gives nothing. I tried MaxRecursion, ...
  • 4,564
2 votes
2 answers
124 views

Entering matrices interactively

I am looking for a way to enter an m*n matrix interactively using a dialog or a Graphical User Interface(GUI). Further, I would like to use this matrix later for ...
0 votes
0 answers
62 views

Why does ListPlot not plot all the points? [closed]

I have a list of {x,y} values that I want to ListPlot. Here is a shortened example: ...
2 votes
1 answer
70 views

List of parameters as argument for Manipulate

Let's say, that we have a list of parameters, that we want to use in manipulate, like so: parameters={{a,0,5},{b,-1,5}}; Of corse you could manually copy and paste ...
3 votes
1 answer
74 views

Assume asymptotic value in a limit?

Is it possible to give Mathematica a limit about's function at infinity? For example I would like to ...
  • 438
1 vote
0 answers
53 views

Fractional Differential Equation

I am facing the following problem. If u[x_,t_]=t+y[t]x, Then, D[u[x,t],t] Gives us 1+xy'[t]. But if I use the command for Fractional Derivative like FractionalD [u[x,t],{t,a}], then Mathematica print ...
1 vote
0 answers
49 views

NDSolve stops solving past a certain time

This is a continuation of the post I've made Unable to solve Delay PDEs Error in Boussinesq Approximation. I apologise if I shouldn't have posted a seperate question for this but I think that the ...
  • 103
6 votes
1 answer
152 views

Round ends for dashes [closed]

I made use of Plot[Sin[x], {x, 0, 2 \[Pi]},PlotStyle -> Directive[AbsoluteDashing[10, 2],AbsoluteThickness[3], CapForm[Round]]] Then I can have It drives me ...
  • 479

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