# All Questions

82 views

### Reading from a socket stream

I noticed an undocumented socket package (SocketLink) in Mathematica (Using version 10, not sure when it was actually added) and wrote a barebones HTTP responder ...
148 views

### Largest matrix size supported by Mathematica 10

I have need to store large square matrices in memory, some times sparse, some times not. I have used up to $2^{15}$ by $2^{15}$ as my upper bound so far, and Mathematica has handled it even if it took ...
36 views

### Sum of derivatives [on hold]

I'm trying to write the expression: $$\sum_{i=1}^3 g_{ii} \partial_i \partial_i f,$$ where $f$ is a function of variables $\{x_1, x_2, x_3\}$ and $g$ is a 3x3 matrix. My expression is: ...
3k views

### Getting the interpolation function from a list plot

I have conducted a chemistry experiment and obtained a list of concentrations of a reactant against time. I plot a graph of this using Mathematica's ListPlot ...
45 views

80 views

### How to render a 3d image of the galaxy? [on hold]

I recently came across the Uniview software package, there has even been a TED talk about it. Here is another example of some interactive views of star maps. In Mathematica 10 AstronomicalData has ...
64 views

### Append plot to existing plot?

I have generated a plot from t=0->1, and I wish to append another plot from t=1->2. How can I do this? Thanks in advance.
47 views

### NDSolve is running an extremely long time: how can I save the existing data?

I am trying to solve a PDE by the following code. It takes 1 hour or so to reach t=25.72 but about 20 hours to reach t=25.72404031638060174049337306126853310997. Actually, the time step is extremely ...
59 views

### ParallelTable and global variables

I want to calculate the convolution of two function. In order to generate variables automatically, I use such an expressions: ...
275 views

### How do I show only the intrinsic color of 3D polygons?

System: Mathematica 9, Windows 7. I want to assign a polygon a color in such a way that it is rendered in that color irrespective of any ambient light sources. In other words I want Yellow to be ...
695 views

### OpenSCAD like functionality with Mathematica?

I keep seeing reference to use of Mathematica as a CAD tool (for instance: http://www.makerbot.com/support/guides/design/). I'd like to use it as such if feasible, but I'm having trouble locating ...
53 views

### Finding the true expectation

I have the density function and I want to determine its expected value ...
84 views

### Creating Scheduler

I am trying to build a scheduler program like pizza delivery. Each driver will choose their time and general working schedule will be updated similarly. Problem is number of workers change. How can ...
60 views

### I need some GPU benchmark for Mathematica

I am considering to buy a GPU. I need to know two things: Is it possible to solve a system of differential equations using GPU and Mathematica's functions? I need to know how much faster would be ...
45 views

### Updating a GUI with ComboBox using GUIKit

Dear Mathematica users, does anyone know how I can update my existing Gui window (made with GUIKit) by choosing different values of a ComboBox so that different and multiple TextFields etc appear ...
145 views

### Exctrating data information from a file.txt

I really did previous long search in the site and I couldn't find any answer that might help me. So I am asking it. I have the following data set, ...
20 views

### Maintain a function quality of an expression [on hold]

I have written a simple code in Mathematica to put a matrix into a vector. The matrix was a function of a variable n, and I want the new vector to also have this quality as a function of n. ...
46 views

### SemanticImport unable to properly read an Excel file with accented letters

Apparently SemanticImport fails to properly import Excel files when accented letters are present in the first (header) row. I'm using Excel 2013 on Windows 8.1 x64 ...
135 views

### FEM - how should I impose periodic boundary conditions in pure space problems?

I have searched other threads, but I was not successful in finding an answer I could understand. Right to the point: how do I impose correctly periodic behavior on the edges of the rectangular ...
293 views

### Maximize[Cos[x - 1], x] is not evaluated

No explanation needed: Maximize[Cos[x + 1], x] Maximize[Cos[x - 1], x] producing ...
138 views

### Understanding SameQ

I am new to Mathematica. So I have read the documentation for comparing expressions in Mathematica and I still don't get the SameQ (===) function. Let me give you a short example: ...
38 views

### Brevity of denoting Conjugate[]

How do I make Conjugate[] expressions have a bar above them instead of Conjugate[ before them, in order to shorted up expressions? I'm looking at something like this screenshot for example:
31 views

### How to join datasets? [on hold]

I have 3 datasets as a lsit: {dataset1,dataset2,dataset3} I want to convert them into a single dataset. The following does not work Join[{dataset1,dataset2,dataset3}] However, this works ...
40 views

### Random generation of three-non-collinear and four-non-coplanar points in 3D space

Please, take a look to this code. How it can be improved so that the time execution becomes smaller? ...
33 views

### Bar legend to Contour Plot

I have a set of 4 contour plots and I show them with the simple Show. How do I present a legend that is the same for the whole set? i.e., the scale needs to truly represent the set and not the values ...
150 views

When I enter ...
32 views

### Generating a Variable Number of Dynamic Variables

I know questions that get at this very issue have been posed in other ways here, but as a relative beginner, I've had trouble understanding the answers. For my application, I am developing a simple ...
52 views

### What's real analogue for FromDigits?

FromDigits only works for integer strings. What's its real-number analogue?
269 views

### Speeding up the non-negativity algorithm for multilinear function with interval probabilities?

The algorithm is a branch-and-bound algorithm that calculates the non-negativity of a multilinear function with interval probabilities. The lines 9-11 has an optimization that is explained on the ...
50 views

### How to use MemberQ for such Variables?

This is NOT the desired out come. I want this test to fail: ...
89 views

### Using VertexDelete to remove vertices by degree

I am trying to remove vertices that have degree less than 2, but I think I am missing something basic. I was hoping that I could use: ...
48 views

### Transform a table (list of associations) to a flat association

I would like to transform a table like ...
110 views

### Discretizing regions with pointy boundaries

I'm trying to discretize a region with "pointy" boundaries to study dielectric breaking on electrodes with pointy surfaces. So far I've tried 3 types of boundaries, but the meshing functions stall ...