# All Questions

38 views

### rescaling X axis

I have a pretty simple code, working fine and producing a plot that is ALMOST what I desire: ...
32 views

### A question on JordanDecomposition in Mathematica

How can I have Mathematica show me also the inverse matrix of the similarity matrix of JordanDecomposition of a matrix? Obviously I need to use here the ...
36 views

### List of Inequalities in RegionPlot with different colors [duplicate]

Starting from the example of the Documentation: RegionPlot[{x^2 < y^3 + 1, y^2 < x^3 + 1}, {x, -2, 5}, {y, -2, 5}] Which gives a nice plot with two ...
30 views

### differentiating an integral [on hold]

I am new to Mathematica. i hope to have the software next week so please excuse the unusual syntax. p(y) means p is a function of y. u(p) means u is a function of p . p(x) is the value of p when y=x ...
124 views

### How to obtain the coordinates of the intersection line of two surfaces?

I can plot the intersection line of two surfaces $f$, $g$ by using: ...
26 views

### Plot3D gives an empty box [on hold]

I have two questions. I am trying to 3d plot a function like in the image below. It gives an empty box displaying no results. I tried adjusting the graphic qualities, but it does no solve the ...
68 views

### Double sum in mathematica

It may look like a stupid question, but I was really confused by how double sums works in mathematica: After simplification, the function actually has nothing to do with n2? Also, when I manually ...
17 views

### Measuring space complexity?

I like using GeneralUtilities function BenchmarkPlot for estimating time complexities, is there something similar for ...
41 views

### Plot for function that calculated direct with while, but is piecewise

For this question Use of {FOR, Do, If,Plot} that ..., I wrote this code: ...
42 views

### Run several input cells in parallel

I have a notebook with several input cells that produce data which is then plotted into separate graphs. Since I do not want to save the results, because it makes the file huge, I keep the ...
120 views

### Definite integration in mathematica

I tried to integrate the following in Mathematica. $\int\limits_{-\infty}^\infty\cfrac{\text{e}^{\text{i}ax}}{x^2-b^2}\text{d}x$ where $a,b>0$ The analytical result is well known. ...
92 views

### To style Sound object

While doing some signal processing research my aesthetic feelings were heavily struck by following output: The problem here is that 211.96 s label is partially ...
77 views

### Use of {FOR, Do, If,Plot} that are in one code? [on hold]

I wrote this code: ...
48 views

### Multiple pattern test in the definition of a function

I have a very simple question, and I'm sure there is a way to do this but I cannot find it: if I want to create a function that's defined only for matrices, I can do it like this: ...
82 views

### Plotting logistic maps

I have a question about plotting in Mathematica in general, and this particular recurrence relation as an example: $\qquad x _{n+1} = rx_{n}(1-x_{n})$ How can I plot the following plots as shown ...
20 views

### Make an existing solution for monitoring parallel jobs robust against dying kernels

Is there any chance to make the solution by @David here http://mathematica.stackexchange.com/a/1562/21606 more robust in the following sense: In my case, some parallel kernels die regularly during ...
33 views

### An unexpected NDSolve behavior [on hold]

I observe the following. The code: ...
28 views

### Setting Initial Conditions in a System of Differential Equations that don't start at t=0

I have a system of six differential equations (linear for the sake of the discussion). I want to set the initial condition to start at time t=18 and not time t=0. I know the values of the dependent ...
32 views

### Importing an .eps file failed in the latest version of mathematica

It was quite straight forward to import an .eps file (also pdf and other formats) into a script, with the version 10.0. that I had before; but, since I upgraded my Mathematica to the latest version ...
53 views

### Matching a Table and a List and building a new Table

I have a Table which includes {Numbers, Probabilities}. For example A= {{1,0.5},{2,0.25}, {3,0.1},{4,0.9}……{100,0.1}}. Put attention that the numbers are 1,2….100 in order. I have a List of random ...
83 views

### How can a function without an operator form be used in postfix form?

As an exercise, I was trying to convert the following Clojure code to Mathematica: ...
54 views

### Using Mathematica to batch-produce text files

I need to make a bunch of plaintext files, all of which differ only in a single parameter. The text I want to "copy" or "batch produce" is a little bit complex, since it contains quoted areas and ...
27 views

### Solving Time-Dependent PDE's Analytically with no non-trivial Boundary Conditions

I'm having some trouble solving a partial differential equation that is supposed to model the propagation of a scalar field in Schwarzschild spacetime using spherical coordinates. I'm using the DSolve ...
29 views

### A function for replacment in mathematica [on hold]

when you have too many replacements such as a1 x+ b2y + c1 z/.{a1->s^2+b^2,b1->r^2+g^2,c1->f^2+k^2} is it possible to define a vector like this ...
65 views

### How can I make an invisible Cell?

Notebooks have a Visible option, but Cell // Options doesn't mention any equivalent for ...
28 views

### how to know two aircraft getting far away each other? [on hold]

Dataset: my algorithm is: calculate velocity vector each aircraft ...
231 views

### How do I encode this replacement rule?

I'm pulling a 5x5 array from a larger array. The small sub-array (call it S) can contain any combination of the symbols A, B or 0. What I'd like to do is: if the array contains any matching pairs ...
46 views

### Why can Mathematica compute numerical sums more efficiently when they are written as matrix operations?

Let $f(n)$ and $K(n,m)$ be functions such that the double sum, which we wish to evaluate numerically, $$\sum_{n=1}^a \sum_{m=1}^a f(n) f(m) K(n,m)$$ exists when $a$ is some large positive number. I ...
42 views

### How to find the concave points of a point-set?

To solve the boundary of a set of planar geometry, I sampled $6$ graphs, then using RunnyKine's approach. ...
39 views

### EventLocator in NDSolve seemingly hogs memory in Windows, but not Mac

I have written a function (ftest in my code) which does the following: Takes a vector {x,vx,vy} as input Numerically solves (with high precision) a specific ...
65 views

### Complicated implicit plotting - can it be tackled?

I'm quite new to Mathematica and have already spent tons of time on problems of this type, browsing through tutorials and topics here. I'm now coming to conclusion that it cannot be done and am about ...
71 views

### What's the easiest way to find the closest point in a list of pairs?

I frequently end up in this situation. I have a solution, but I suspect it's the dumbest way of doing it. Frequently, I'll have a list of pairs, for example: ...
56 views

### Learning Mathematica for Math Majors [duplicate]

I just downloaded Mathematica and I'm taking a course in Multivariable Calculus. I realize there is a lot of complexity to Mathematica and there are Many types of learning resources out there. I was ...
166 views

### NDEigensystem returns incorrect eigenvalues for 2D coulomb problem, eigenfunctions contain discontinuity

I posted a similar question a short time ago regarding the 3D Coulomb problem. Jens' excellent answer to this thread allowed me to obtain the correct eigenvalues and eigenenergies for that system. I ...
70 views

### Plotting a convex hull with a coordinate mesh

I am plotting the convex hull of some curves by extracting the curves from a contour plot and constructing the convex hull around their discretized version . It's not terribly accurate for ...
100 views

### Seeing coordinates in Graphics3D

I'm writing some structures built up from different strings that specify the coordinates of the lines. The code used to generate these is built up from a ton of user defined functions from my library, ...
51 views

### CopyToClipboard freezes FrontEnd

This is freezing the FrontEnd: CopyToClipboard@ExampleData[{"Text", "AeneidEnglish"}] Are there system limits I'm hitting here?
65 views

### Prevent evaluation after ToExpression

How can I produce both typesetting and evaluation of a LaTeX expression? Illustrative example: The evaluation of HoldForm[Sqrt[2.0]] == Sqrt[2.0] looks ok (aside ...
59 views

### what is wrong with this plotting code? [on hold]

Heres the question: The region bounded by f(x) = x+2 and g(x) = sin(x) between x = 0 and x = Pi/2 i. Plot the region on the interval [0,Pi/2], between y = 0 and y = 4. ii. Find the area of the ...
43 views

### Change “ListPlot” to 16 bit accuracy? [on hold]

I have (with the help of this forum) managed to plot a bifurcation diagram with the following code: ...
79 views

### Define a 4d matrix without for loop

I was wondering if there is a way to avoid for loop here: I want to define a 4d matrix H(i,j,k,l), and each entry in the matrix is calculated through a complex function, say Do_H(i,j,k,l), depending ...
26 views

### FindPeaks error “ Expecting an image or graphics instead of”

I'm running Mathematica 10.3.1.0 on windows 7 Professional Sp.1 when I try to use FindPeaks I keep getting the following error, even when trying the example in the ...
62 views

### Huge difference after changing a fraction to decimal

I have a limit to calculate. With[{p = 1/2, q = 0.1}, Limit[a^q Integrate[Sin[x]/x^p, {x, a, Infinity}], a -> Infinity]] gives correct result ...
56 views

### Can you help me reduce this? WolframAlpha's search bar has a character limit [on hold]

Trying to find the pursuit curve for the following illustration: First equation of motion: ...
21 views

### How to derive natural boundary conditions and governing equations by Mathematica [on hold]

I can derive governing equations of system by Variational Package of Mathematica but it doesn't give boundary conditions. How can i get them? or is there another way (such as another software) to do ...
42 views

### NDSolve won't stop running [on hold]

I'm trying to solve the wave equation with NDSolve, but everytime I hit evaluate notebook it won't stop running. Any insights? ...
30 views

### Time and distance problem [on hold]

A train starts from Jammu for Srinagar at 13:30 and reaches Srinagar at 17:30. Another train starts from Srinagar at 15:30 and reaches Jammu at 19:00. At what time will the trains meet?. I have ...
38 views

### axis label problem

I have a contourplot with (Greek) omega on the y-axis and Q^2 (GeV^2) on the x-axis. When I do ...