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### Maximize finds solution outside the constraint

I'm trying to maximize a (quite simple) polynomial inside a sphere. The command is simply: ...
32 views

### How to make conditions works in Which?

How to make Condition convert to common expresstions when it mathes Which test. ...
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### Finding Lyapunov exponents from Hamilton formalism

I have the following Mathematica code to find the Lyapunov exponents for a given Hamiltonian. I use an algorithm developed by ChrisK for my code given below: ...
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### Custom (semi-circle) distribution not playing well with RandomVariate?

I have created a custom probability distribution that is a semi circle with area 1: myD = ProbabilityDistribution[Sqrt[2/Pi - x^2], {x, -Sqrt[2/Pi], Sqrt[2/Pi]}] I ...
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1 vote
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### Changed behaviour of Interpolation

Consider the following code: Interpolation[Table[{i, 2 i}, {i, 10}], InterpolationOrder -> 1][{5}] Mathematica 13.2 on Windows 11 returns ...
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### How to make a smoothed 3D histogram from data contained in a large file on my Mac computer

The original data is in a file "ABC" in a directory on my Mac computer. ABC has 20000 lines, each line has 2 real numbers. How do I import this file into Mathematica and pass it to ...
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### How to determine a timeout in loop and truncate the loop?

I have a Do loop with a single sentence in it: Do[ (*A single sentence here*) ,{i,100}] Unfortunately, this sentence could be very time-consuming, so I want to set ...
18 views

### How to Find the Subspace of 𝐵 B Excluded from 𝑄 Q-Image and Kernel? [migrated]

Let A, B, and C be three vector spaces, and consider a map Q that takes vectors from A to vectors in B, and from B to vectors in C. One could think this map as a matrix acts on vectors in A and B. A ...
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I'm solving two sets of equations, the equations are given below, $-\frac{t'[\lambda]}{z[\lambda]^{2}}+\frac{z'[\lambda]^2}{z[\lambda]^2}=1$ t'[\lambda]^2=\frac{p^2 z[\lambda]^{2}z'[\lambda]^2}{1+p^2 ... 1 vote 0 answers 40 views ### Poincare section for a cigar shaped geometry Here is the mathematica code that I am using to find the Poincare Section of a Cigar Shaped AdS-soliton background: ... • 2,523 2 votes 0 answers 58 views ### Can't compile a standalone app in 14.1 I read the article reviewing the innovations in version 14.1 and am absolutely thrilled to be able to build a standalone app. I tried to replicate the example from the article in an even shorter form, ... • 740 0 votes 0 answers 42 views ### How to color contour lines with functions [duplicate] For example: a Implicit functions X^2 + y^2 == 1, i want to plot it and color it with function x + y to display the size of x + y in different positions on this Implicit functions. What should i do? ... 0 votes 0 answers 45 views ### How to change the default behavior of a function permanently? For example, I want the function Animate to work with options ... • 141 0 votes 0 answers 22 views ### How to hide regionfunction [duplicate] I just want to show the part of the cylinder and hide the transparent regionfunction.What should I do? 0 votes 1 answer 74 views ### NMinimize finds solutions outside of the constraint set I have a feasible compact convex program of the form: \begin{aligned}\min_{\substack{x_i\in[0,1]\\z_i\in[x_i^3,x_i]}}&\quad\quad\sum_{i=1}^n a_iz_i+d_ix_i\\\text{s.t.}&\quad\quad\sum_{i=1}^n ... • 136 0 votes 1 answer 50 views ### Pressing Ctrl+( with highlighted text converts them into some markup code and won't undo I am new to Mathematica, and I am using Mathematica v12.3. I am writing some math notes which include text and some equations. I know that in a text cell I can press CTRL+( and start typing some ... • 101 2 votes 0 answers 47 views ### How to generate lensed light animations like this? How can one generate the projection simulation effect in the following video (from Apple's webpage (minus the logo of course)). I would like to be able to create a similar-looking shader animation in ... • 31.7k 1 vote 1 answer 58 views ### NMaximize::ntcnvx: The optimization was not solved by convex methods I have a complex (but still finite-dimensional convex) program in mind for which I want to use Mathematica to solve numerically. For this reason, I was trying my hand on simpler instances. Consider ... • 136 0 votes 0 answers 55 views ### Plotting solution of a 3 body problem with given initial conditions Disclaimer:I am not trying to find new solutions for the 3 body problem (3bp), I already have the initial conditions and I already know what configuration I should get. I am trying to create an ... 3 votes 1 answer 100 views ### How to delete members of a list by rule I have a list: lis = {"a",1,""} and would like to delete from the list all elements that consist of "" to give: ... • 5,005 0 votes 0 answers 40 views ### Inbuilt function in NonlinearModelFit Can you please tell me about the inbuilt function in NonlinearModelFit? Is it related to least-square fit? If yes, please describe. ... 0 votes 0 answers 84 views ### I discovered this pattern for factorials - does it hold true for all factorials? [closed] Code that reproduce (with corrections) the original post: ... 3 votes 1 answer 109 views ### How can I draw triangles within in a triangle if I know their perimeters? I am trying to draw this picture with perimeters of the triangles in a larger triangle. I don't know how to start. • 1,118 0 votes 0 answers 49 views ### 4D Poincare surface of sections I'm trying to plot 4D Poincare surface of sections. I have integrated the equations of motion, and I also know how to plot 2D Poincare surface of scetion, but facing difficult in plotting 4D. In 4D ... • 87 1 vote 1 answer 103 views ### Solve and understand a NDSolve error: Step Size effectively zero; singularity or stiff system suspected I am trying to solve the non-linear differential equation: \ddot{x}(t) =\frac{3kx(t)}{\gamma^2}\left[kx^4(t)-2 \right] $$numerically on Mathematica, but I can not find a solution. My code is: <... • 13 0 votes 0 answers 55 views ### Why Won't My Functions Plot? [closed] I've been trying to graph a function with a domain between [-4Pi,4Pi], but the function can't be graphed as soon as I add Pi to the domain: So what's the issue here? Is there a workaround for this? 1 vote 1 answer 40 views ### Using Collect on constant terms within an equation with derivative terms I would like to use the Collect[] function to gather terms that have the same powers for some constant parameter a. For example: ... 0 votes 1 answer 94 views ### Rsolve is not working (a(n) too difficult to find?) ... 2 votes 1 answer 121 views ### Weird error in RegionPlot3D? I am trying to plot a sphere with radius varying with the angles. Here is the code ... 0 votes 0 answers 33 views ### RSolve for a recurrence relation with Kronecker-Delta and its closed form Assume the following recurrence relation for n\ge 0 $$(\gamma+x(2n+1)) a_n=x (n+1) a_{n+1} + x n a_{n-1}+ x (\delta_{n,0}-\delta_{n-1,0})$$ This recurrence relation ... • 29 1 vote 0 answers 68 views ### Mathematica just returns the same equation when asked to solve integral equation of Volterra I am new to Mathematica. I try to compile the example shown in this article After copying and pasting the first two lines, and then pressing Shift + Enter, the program always returns the initial ... 0 votes 2 answers 131 views ### A probability problem involving no replacement Question: There are 6 identical balls, numbered 1, 2, 3, 4, 5, 6. Three balls are drawn successively without replacement. Let m be the average of the numbers on the first two balls drawn, and let n be ... • 4,832 0 votes 0 answers 36 views ### FindSequenceFunction[] fails to infer a sequence pattern I have to compute the following function:$$\sum _{i=0}^{\infty } \left(1-\sum _{j=0}^{\min (i,2 n)} \frac{n^{-i} \Gamma (j+1) \Gamma (n+1) 2^{-i-j+2 n} \mathcal{S}_i^{(j)}}{\Gamma (j-n+1) \Gamma (-j+... • 197 3 votes 1 answer 134 views ### Using NDSolve to solve the PDEs and their reduced ODEs yields inconsistent results I am working with a system of coupled PDEs: \begin{align} \partial_tP_x(t,x)&=(\omega_0+\gamma gx)P_y(t,x)-P_x(t,x)/T_2+D\partial_x^2P_x(t,x)\\ \partial_tP_y(t,x)&=-(\omega_0+\gamma gx)P_x(t,x)... • 451 0 votes 0 answers 35 views ### How to speed up Factor? Try the following code ... • 581 0 votes 0 answers 27 views ### Fourier transform of a symbolic function In Mathematica: How can I compute the Fourier transform of a symbolic functionx\partial_y f(x,y)$?. I know that,$(x\partial_y f(x,y))^{\wedge}(\xi,\eta)=\xi \partial_\eta \widehat{f}(\xi,\eta)$. • 203 0 votes 0 answers 36 views ### Different computer hardware give very different NIntegrate result? If two computers are running Mathematica with the same version "14.1.0 for Microsoft Windows (64-bit) (July 16, 2024)" and all the NIntegrate options are ... 1 vote 0 answers 61 views ### Why is the solution to a harmonic equation split into two classes when one class suffices? If we solve$\sin(x) = 0$, we arrive at $$x = n \pi, n \in \mathbb{Z}$$ When I do (Reduce also returns the same) Solve[Sin[x] == 0, {x}, Reals] The result is $$\{... • 3,420 1 vote 0 answers 67 views ### With both 14.0 and 14.1 Save as PDF (print preview) has become completely mangled For over a decade, I have been using the same method of creating and saving notebooks as PDF. For some reason saving to PDF started to produce complete gibberish for most of the styles I use. It ... • 1,577 1 vote 1 answer 47 views ### How to make Simplify run faster So I have the function of an arbitrarily oriented torus and I wanted to run simplify on it to see if mathematica can find any simplifications on it. But Simplify ... • 143 0 votes 0 answers 19 views ### Temporary directories left behind by the CreateArchive function The CreateArchive function sometimes leaves empty subdirectories of the form m_x in the destination directory, where x is a ten-digit alphanumeric identifier that ... • 91 2 votes 1 answer 46 views ### How to sum with respect to partitions I would like to know how to program this type of sums, with the first two values whatever I want S_{k}(0)=m and S_{k}(1)=t, and for n>0:$$S_{k}(n+1)= \sum_{r_{1}+r_{2}+\cdots +r_{k}=n}S_{k}(r_{... 0 votes 0 answers 48 views ### How to stop the cursor from jumping out of parentheses/brackets/braces I am having an issue that is seriously impacting my ability to fluently write code in wolframnotebook 14.1. Whenever my cursor is just behind an opening bracket/parenthesis/brace, it automatically ... 1 vote 0 answers 98 views ### What is Mathematica's equivalent of Maple's package algcurves? Maple has a package called algcurves for plane algebraic curves, providing some powerful functions. For instance, it can compute a basis for holomorphic differentials, locate all singularities, ... 1 vote 1 answer 53 views ### Why is the accuracy of NSolve's solutions for equations with multiple roots lower than the accuracy of the original coefficients? Try the following code ... • 581 1 vote 1 answer 39 views ### Unevaluated indexed variable in the events when using Table or Array generating a list of events [duplicate] I want to use Table or Array to generate a list of events for NDSolve, but the variables (<... • 1,467 1 vote 2 answers 123 views ### Issue with variable within Sum[] bounds I have the following sum that starts from a variable lower bound index$n\$: $$\sum _{y=n}^x \frac{n^2! \left(n^2\right)^{-x} \mathcal{S}_x^{(y)}}{\left(n^2-y\right)!}$$ I tried to compute a closed ...
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As far as I see there is no single thing on the internet with errorcode MapThread::mptd being associated with the Labeled ...
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### Sum[] function not computing the sum

I have the following sum: $$\sum _{y=0}^x \left(1-n^2! \left(n^2\right)^{-y} \mathcal{S}_y^{\left(n^2\right)}\right)$$ Which, in Wolfram language can be written as: ...
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