# All Questions

53 views

### Fourier-style solutions to differential equations, not piecewise polynomials

NDSolve returns piecewise polynomials. Is there any way I can get a single (non piecewise) function consisting of sines and cosines instead? Sort of a "Fourier approximation" to the solution of my ...
202 views

### Plot of $\sin(x^x)$ is missing from $x=143$

When plotting the graph of $\sin(x^x)$ I noticed that there is no plot from about $x=143$. I don't suppose there is a purely mathematical explanation for this? So, why is there no graph in ...
75 views

### Phase space of a system of differential equation

I have a system of three Coupled nonlinear equation of a physical system and i would like to plot the phase space. My system is a chaotic system dependant of three variable dependant of time (l1, ...
67 views

### Problems with QueueingNetworkProcess [closed]

I have a two stage queueing network and want to vary the number of servers at the second node. The input data and the Manipulate command is below: ...
69 views

### Possible memory leak in FindMinimum? (MMA v10.0)

So I was running some code when I noticed Mathematica was gulping memory, and after some debugging I think the culprit is found. It turned out the function ...
153 views

### Symbolic vs numerical integration

This is related to a question that I asked before but didn't resolve quite well. I want to obtain the solution of the following expression analytically: ...
33 views

I want to write a SystemDialogInput function that allows user to choose a file from a directory. In the directory, there are two kinds of image files: Atom images: The name of the file is in the ...
85 views

### MeshRefinementFunction missing points

I'm doing some FEM on a rectangular region with a spherical cavity: ...
57 views

### How to refer a number in a list with two columns, first one is a number and the second one is empty? [closed]

Let's say, I have defined a list as list = {{-31, -31}, {52, }, {34, -11}, {-38, }, {78, -44}, {-36,14}, {-9, 98}, {33, 6}, {82, 99}, {-85, -10}} As you can see, ...
351 views

### How to extract a contour line (or a region) from a ContourPlot?

Given a ContourPlot with a set of contours, say, this: is it possible to get the contours separating domains with the different colors in the form of lists? ...
31 views

### Changing from Cartesian to polar coordinates in partial differential equation [duplicate]

I have a partial differential equation: $$\left(x^2+y^2\right)\frac{{{\partial ^2}u(x,y)}}{{\partial {x^2}}} + x^2\frac{{{\partial ^2}u(x,y)}}{{\partial {y^2}}}=0$$ How to change from Cartesian to ...
117 views

### Add terms to nested list

Suppose I have a nested list of the following: list={{1,2},{5,8},{4,1}...} I would like to add a number to each first term of the list. The output would be ...
89 views

### Automatic text-wrapping in labels in TimelinePlot

Part-related to this question and part-related to this one, I would like to make use of the new features of TimelinePlot in 10.3, but would like to incorporate some ...
27 views

### Length in Compile encounter “type Integer encountered in assignment of Type Real ”

Compile[{}, Module[{n}, n = Length[{1, 2, 3, 4}]; n = n/2]] The above code will emit errors Compile::cset: Variable n of type _Integer encountered in ...
56 views

### ParallelTable should distribute dedicated evaluation range to different kernels

I have 4 kernels and would like that in ParallelTable: ...
61 views

### How to solve for the eigenvalue in matrix? [closed]

For which value of $a$ in the matrix {{a,2}, {3,4}} has the matrix eigenvalue of $0$? How to solve it in Mathematica?
196 views

### How to generate two group of $n$ random numbers in $U(0,1)$ such that sum of these two groups equal? [closed]

I want to have two groups of $n$ random numbers $u_i$ and $v_i$ in $U(0,1)$, such that $\sum u_i = \sum v_i$ What I tried is: I can firstly get $u_i$ by ...
24 views

### Why can't I change the Magnification in Printout Style in Default.nb

This happens with Mathermatica 10.3.1.0: When working with a notebook, I can choose between different working environments. However, they inherit their settings from Default.nb situated at ...
45 views

...
97 views

...
95 views

### I want to plot a list of points with specified t and x[t] coordinates [closed]

I have this code: ...
68 views

74 views

### How to solve this recursive system?

I try to solve the equation system as ...
60 views

### Notebook Magnification changes - Why?

I have written a notebook but in order to edit it, I prefer 125% magification or even 150%. I know Window>Magnification. Also there is a small symbol on the right bottom of the notebook, where I can ...
44 views

### Need Help with solve function [closed]

I'm trying to re-write this function x = e^(-(r+(1/2)*sigma^2)*t-(g)(sigma)*sqrt(t)), as an expression of "g" instead of "x" ...
233 views

### Follow each pixel brightness in set of images (Memory constrained)

I have a set of 2700 consecutive png images (8bit, 2048*2048 pixels). I would like to visualize the intensity variation of each pixel vs. image number. Here is an example of 10 images: ...
40 views

### Possible Bug with DateObject

So my questions is going to be hard to duplicate because I am not sure when or why it happens. I've read here several bugs with DateObject, but none of them ...