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Plotting mass spectrum of states

How can I obtain the following plot via Mathematica? I have my own data but I couldn't have obtained the plot. Thank you for your help
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2 votes
3 answers
83 views

Solve and equation containing $\sinh$ and $\cosh$

I want to know how I can solve this or plot a versus b ? Solve[ Sqrt[a] Cosh[1.2 Log[1.65 Sqrt[1/a]]] == Sqrt[-b] Sinh[1.2 Log[1.65 Sqrt[-(1/b)]]], b] Thanks
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2 votes
2 answers
270 views

How do I implement convolution integrals symbolically (not numerically)? [closed]

I'm working to symbolically solve convolution integrals i.e., using symbolic equations and not numerical methods of integration. The general form of the convolution I'm working to solve is as follows: ...
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3 votes
2 answers
98 views

Unexpected behaviour of Condition with Cases/MatchQ?

When using the unsorted version of Complement in this question I met the following unexpected result, ...
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  • 31
3 votes
2 answers
57 views

How do I integrate this piecewise function with Mathematica?

I came across the question of what percent of numbers from 0 to 1 have a logerithm whose floor is even. What I did was I made a piecewise function: ...
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2 votes
3 answers
103 views

Infinite Integral involving a Bessel function

I have trouble evaluating the following numerical integral, $$ \int_{0}^{\infty} d k^{(yz)} \, k^{(yz)} J_{0} \left(d^{(yz)} k^{(yz)} \right) \frac{e^{-i d_x \sqrt{k_R^2 + {k^{(yz)}}^{2} }}}{ \sqrt{...
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  • 83
2 votes
3 answers
102 views

Divide string into a sublist of sentence with the maximum number of character

Context: I have a long article (on Wordpress). And I'm using Google Translate API (v2) to translate this article. This article has about 300 000 characters. However, due to the limit of Google ...
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  • 1,641
3 votes
1 answer
41 views

Why doesn't ListPointPlot3D plot a Table's output that iterates over three variables? [closed]

Why does ListPointPlot3D accept tables with 3 outputs and 2 variables such as: ...
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9 votes
0 answers
116 views

Reduce: Var is not a valid variable

Bug introduced in 12.3 or earlier and persisting through 13.0.1 or later I am trying to integrate the following but it returns a Reduce::ivar warning message. ...
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  • 1,123
0 votes
1 answer
104 views

Small question about the output form of the derivative

I have an expression: D[D[Subscript[T, 1][x[t], y[t], x'[t]] + Subscript[T, 2][x[t], y[t], y'[t]], x'[t]], t] The result is: $y'(t) T_1{}^{(0,1,1)}\left(x(t),y(t),...
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  • 1,721
1 vote
0 answers
93 views

Mathematica can not interpret parentheses correctly [closed]

I want to sum up four terms but Mathematica does not interpret the parentheses correctly. In the picture, in second line there is only one term that starts with 1/12...
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0 votes
0 answers
63 views

Problem with DSolve

I'm trying to solve a system of equations with DSolve, but Mathematica is neither giving any output nor showing any error. However, if I solve this system with <...
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  • 87
2 votes
2 answers
123 views

Solve singular fourth order ODE

I am interested in solving the following differential equation : $$ \left(\frac{300 i}{r^{5}}-\frac{3}{r^{4}}\right) \psi(r)+\left(-\frac{45}{r^{6}}+\frac{3}{r^{3}}\right) \psi^{\prime}(r)+\left(\frac{...
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  • 345
3 votes
2 answers
132 views

FunctionPeriod for functions defined in a Piecewise manner

To create a minimal example, consider a piecewise function: ...
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  • 16.2k
2 votes
1 answer
119 views

How to give a property to a list of functions?

For example, I have defined a bunch of binary functions Sum1, Sum2, Prod1, ...
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0 votes
0 answers
50 views

Minimum of a function that depends on several variables

I have a function, $$A=\sum_{m}mx$$ provided $$x=\frac{2(y1+iz)}{2t1-\left|\frac{t2}{iy2}+z\right|}$$ Here $$y1,z,t1,t2,y2$$ all are varying. But $x$ needs to be in the limit of $-1$ and $0$. Is there ...
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  • 1,163
0 votes
0 answers
45 views

Function aborts when inside manipulate

I have a function that completes without problems, as shown here. VisualizeRx[textimage, "test", 1, 0, 0, "WriteFiles" -> False]; But when ...
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  • 1,857
8 votes
1 answer
104 views

How to get a membership condition for RegionBoundary using RegionMember

This is my first question on this forum, but by no means my first problem with Mathematica (which I've been using daily for years). Consider ...
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2 votes
0 answers
58 views

In an element of a matrix, can I refer in an element to its own row or column? [closed]

In an expression inside the matrix, can I obtain the indices of the element where this expression is located? Also, can I refer to other elements of that same matrix, like in spreadsheets?
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  • 2,751
0 votes
1 answer
117 views

How to solve 2D Heat equation on rectangle with NDSolve?

I am trying to solve the 2D heat equation $$\Delta u =u_t$$ with Dirichlet boundary conditions on the rectangle $(0,a)\times (0,b)$ and with initial condition $u(x,y,0)=g(x,y)$. This is my code ...
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  • 125
5 votes
3 answers
267 views

Linear ODEs with NDSolve

I am trying to solve some first order linear odes. My code is below: ...
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0 votes
1 answer
105 views

Heat Equation with Mobile Boundary

I am trying to use NDSolve to find the solution to a set of coupled diffEQs. They represent 1d (radial) heat balance in a spherical shell. The goal is to specify a heat flux into the base of the shell,...
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  • 123
3 votes
2 answers
293 views

Why do I get a different answer from Mathematica when calculating this integral?

I am curious and confused about the solution of this integral. $$\int_{t}^{T}(1-e^{\alpha(s-T)})e^{\alpha(t-s)}ds$$ When I use Mathematica with this code ...
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10 votes
1 answer
364 views

Can Mathematica read planar graphs with pc format?

We can download files about some special planar graphs at the following website, but their files are suffixed with pc. http://users.cecs.anu.edu.au/~bdm/data/planegraphs.html I don't know how to ...
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  • 763
1 vote
0 answers
63 views

Three nonlinearly coupled PDEs

I am new to Mathematica and I need it to solve a system of three nonlinearly coupled PDEs. $\frac{n_1}{c_0} \frac{\partial E_1}{\partial t}+\frac{\partial E_1}{\partial x} = i\frac{\omega_1}{2n_1 c_0} ...
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  • 11
1 vote
0 answers
65 views

Possible bug: Wrong limit for `EllipticE`?

I encountered problem with computing limits of Elliptic functions E and F. For example, ...
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0 votes
0 answers
59 views

Assigning code to a function makes it stop working

I know its a lot, but please bare with me I'll explain it step by step I have a rare situation; as said in the question, I wrote a certain code, that runs perfectly by itself. However, since I need to ...
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0 votes
0 answers
65 views

How to do this recursion relation in Mathematica effectively?

I have a function $h_{\Delta,l}(r,\eta)$ satisfying \begin{equation} h_{\Delta,l}(r,\eta)=\tilde{h}_{l}(r,\eta)+\sum_{k}\frac{c(k)}{\Delta-(1-l-k)}r^{k}h_{1-l+k,l+k}(r,\eta) \end{equation} where $k$ ...
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  • 51
10 votes
3 answers
360 views

Mapping a numerical array of numbers onto the surface of f(x,y) possible?

I'm considering mapping an error estimate matrix onto the surface of a function f(x,y) in the indicated range: ...
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  • 1,114
4 votes
1 answer
41 views

Timing Discontinuity with Replace[] Function

When constructing certain square matrices I noticed a sharp jump in the time required to build them. I've included code and a plot of time required to make the matrix vs dimensionality of the matrix. ...
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2 votes
2 answers
57 views

ListLinePlot not showing one label in a cycle of points

I am using ListLinePlot to represent a closed circuit of points (forming a polyhedron). I am trying to label each node (point) of the cycle, but the node that is ...
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  • 1,057
2 votes
1 answer
33 views

Plot a region between two curves that is below another in $R^3$

I am trying to obtain a 3D plot of $z=x^2+2y^2$ that is bound by the region in the $z=0$ plane governed by the equations $y=x$ and $y=x^2$. Is it possible to do this with ...
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  • 33
5 votes
4 answers
572 views

Replacing large numbers

Imagine I have the following list l = {{1,2,3},{4,10^(16),5}} How do I efficiently replace the large number by a number (zero, for example). I can't seem to do it ...
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  • 4,228
4 votes
1 answer
248 views

Weird behavior of Derivative

I have noticed a weird behavior of the "Derivative" operator, and I would like to know to why is this happening and if it is intended, as I'm using this function quite a bit in my code and I ...
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  • 261
1 vote
0 answers
63 views

It is possible to call C functions with pointers as arguments in Mathematica?

Here is my goal: I want to call external library functions, written in C (not by me), in Mathematica. I may have found a way to do it using LibraryLink by following this scheme: First, for each ...
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  • 151
1 vote
3 answers
124 views

How can I get these decimals formatted properly?

It's nothing serious, but I was just wondering. I have a large number of floating point numbers which I write to a file. Mathematica writes each number with 17 decimal positions, which is way more ...
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  • 6,638
1 vote
1 answer
68 views

Series Expansion of EllipticNomeQ differs from older Mathematica Version

I am trying to follow the numerical approach on how to calculate EllipticE and EllipticK following this paper. In there on ...
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  • 4,437
1 vote
2 answers
41 views

Find min value of a complex Root function [closed]

Could someone tell me how to obtain the min value of this function when lambda is between 0 and 1: ...
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  • 11
8 votes
2 answers
111 views

Constructing a RootSum object changes existing internal syntax

Bug introduced in 9.0 or earlier and persisting through 13.0.1 or later I noticed that initially valid syntax becomes invalid within nested RootSum objects. ...
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  • 2,929
1 vote
0 answers
33 views

How to authomatically extract info from error messages [duplicate]

I am using NDSolve to compute particles' trajectories. Typically, I get an error of the type: NDSolve::ndsz: At t == 0.11880535502829011`, step size is effectively zero; singularity or stiff system ...
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1 vote
0 answers
44 views

How To Fit Heston Model To Stock Data Stochastic Volatility Model

The stochastic volatility model known as the Heston model can be expressed in Mathematica in the following way https://reference.wolfram.com/language/example/HestonModel.html Define the Ito process of ...
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0 votes
0 answers
41 views

A way to tell mathematica to not alphabetically order second derivatives

I have a frame of vector fields $E_1 ,... ,E_6$ and it's convenient for me to write $E_1(f)$ as Dt[f,e1] where e1 is an ...
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0 votes
0 answers
31 views

Graphing multiple functions on the same graph using AbsArgPlot, but the colour of the graphs keep coming up grey

I am trying to create a plot of the modulus of the eigenvalues of an associated matrix that is parameterised by sigma. When plotting a single eigenvalue using AbsArgPlot, the graph is coloured nicely ...
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  • 1
1 vote
2 answers
77 views

Change the Filling order

I want to this: from this picture ,can find that "red" in front of "blue" My code: ...
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2 votes
1 answer
126 views

Stop Mathematica’s automatic indentation on existing notebooks

This question relates to Mathematica 12.3 (and possibly many other versions). Mathematica's automatic indentation does not conform to my workflow. From the very old days of Mathematica 1.2, i.e. ...
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1 vote
2 answers
146 views

Finding and plotting solutions of a complex function

I have a complex function given by f1 = Sqrt[-16 x^4 - 16 y^4 - 16 z^4 - 32 I x^3 \[Pi] + 24 x^2 \[Pi]^2 + 8 I x \[Pi]^3 - \[Pi]^4] When I plot the real part of ...
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  • 577
1 vote
0 answers
85 views

NDSolve for complex pde

My goal is to use NDSolve to solve the complex pde $F(z,t)$ with complex derivative $\partial_{z}=\frac{1}{2}(\partial_{x}-i \partial_{y}).$ The equation can be ...
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2 votes
2 answers
126 views

PlotStyle for GridLines

I have: Plot[x^2,{x, 0, 5},GridLines->{{3,4}},PlotRange->{5,30},PlotStyle->{Black,Dotted,Thickness[0.003]}] How to make these two vertical lines in style ...
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1 vote
0 answers
46 views

How to simplify a function imposing that it is equal to zero?

I have a function calculated by Mathematica given by $F=\frac{1}{2r^3}sin[\theta]Y^{(1,0)}[\theta, \phi]((-4m+L(1+L)r)h0[t,r]+r(-2m+r)(-rh0^{(0,2)}[t,r]+2h1^{(1,0)}[t,r]+rh1^{(1,1)}[t,r]))$ and I want ...
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0 votes
0 answers
56 views

Solving second order non-linear DE with boundary condition

I was trying to get some result from this equation but I can't find the solution. please see what is wrong with it??!! thanks f, s are positive and k will be negative or positive. ...
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