# All Questions

298 views

### Force integration to be linear over sum?

Is there an obvious way to force Mathematica to separately integrate the terms in a sum? According to the docs, When part of a sum cannot be integrated explicitly, the whole sum will stay ...
288 views

### Fourier-Motzkin Elimination

Is there any method available in mathematica to eliminate variable from set of inequalities? I tried Eliminate function available, but I guess it works on equalities only.
522 views

### Highlight integer points in RegionPlot

Is there any way to mark integer points after plotting region in Mathematica? For example, if I: ...
171 views

### How to control dependent PopupMenus?

I created three interdependent PopupMenus with names demographic, region and ...
280 views

214 views

### Functions that operate on symbolic matrices?

I'd like to write functions that operate on symbolic matrices, and do nothing when fed anything else. ...
245 views

### Return partial result when MemoryConstrained aborts NDSolve

I use NDSolve to solve a large set (~400) of coupled ODEs. Sometimes, the memory (~4GB) gets filled up, and my computer becomes impossible to work with, because it ...
345 views

### Simple blink comparator for two images

I tried to build a simple 'blink comparator' - where you can click on an image repeatedly to switch between two similar images. (An old-fashioned notion in the days of powerful image processing ...
623 views

### Mathematica 9 does not read mathematica 8 “.mx” files

Having written a lot of code on M8, I recently switched to M9 and tried to run the code on M9, the code starts by loading an .mx file written by M8, but M9 wouldn't read the .mx file saying that it ...
293 views

### Multiple instrument chord

I would like to create a chord using multiple instruments. This started as an attempt to explain music to a friend but my curiosity has taken over. I am familiar with the SoundNote function. I know ...
236 views

### Exporting as .PDB extension

I am working with the 3-D coordinates of proteins. The file format I import and modify coordinates of is in the .PDB format, and the string to import is also in this same format. Currently, when I try ...
175 views

### How to use Optional as an omissible parameter in pattern-match?

Below is a function intended to test if an expression is a polynomial in which all the coefficients and exponents are integers: ...
364 views

### Relative error plot [duplicate]

I was plotting the relative error of the $e^{11/12 -n}n^{n+1/2}$ approximation to $n!$ as $n$ gets larger and larger, and at some very large value of $n$ Mathematica gives this plot: Can somebody ...
809 views

### How do I prevent fonts sizes and line weights from scaling in exported graphics?

It's common to export graphics from Mathematica that are subsequently scaled to various sizes that cannot (at least not conveniently) be anticipated. This is problematic in cases where (as is common) ...
325 views

### Verifying and deriving basic (block) matrix identities

How can I use the new symbolic matrix/tensor capabilities to verify matrix identities, such as (1) or (2) Even better, how can I ask Mathematica to derive expressions for X, Y, Z, and U like ...
599 views

### Solving/Reducing equations in $\mathbb{Z}/p\mathbb{Z}$

I was trying to find all the numbers $n$ for which $2^n=n\mod 10^k$ using Mathematica. My first try: Reduce[2^n == n, n, Modulus -> 100] However, I receive ...
252 views

### Simplify the multiplication such as $a*(b+c)$ to $a*b+a*c$

I am trying to solve this problem here but have to understand basics. Suppose I have a multiplication such as $a*(b+c+d+...+x)$. How can I multiply it to the result $a*b+a*c+...+a*x$? Trials ...
428 views

### Removing an extra curly braces when using Grid with an If statment

I use Grid to align controls in Manipulate. Here is a simple example ...
4k views

### Solving the Travelling Salesman Problem

I've been trying to find some kind of mathematical computer software to solve the Travelling Salesman Problem. The Excel Solver is able to do it, but I've noticed there is a built-in function in ...
282 views

### How to solve this combination equation?

I want to solve the equation $$2n\cdot\binom{n}{0} + 5(n-1)\binom{n}{1}+13(n-2)\binom{n}{2}+\cdots + \left(2^{n-1} + 3^{n-1}\right)\binom{n}{n-1} = 1685.$$ or using alternative notion for binomial ...
210 views

### Need Help Writing (a Pascal) Matrix in Mathematica

I want to write a function $f[n]$ in Mathematica which gives me an $n\times n$ lower triangular Pascal matrix with a row of zeros in between each nonzero row. That is, I want the matrices ...
814 views

### How can I understand the result Mathematica returns from DSolve?

I have solved an ODE using DSolve, but I have a problem with understanding the solution. In general the solution is in the form: ...
680 views

### Exact cover solution

Is it possible to get a exact cover solution(s) and/or number of possible solutions in Mathematica?
305 views

### Microsoft SQL DatabaseLink connection using Windows Authentication from Mac

We know that Mathematic doesn't natively support Windows Authentication connect. But as we can see in this post, the problem can be easily solved when your Mathematica is in Windows version (I have ...
231 views

### How to make this code threadsafe?

I have the following code, schematically: ...
535 views

### a problem about simplifing conjugate

the situation is as follows ...
650 views

### Counting radial ridges on an image

After happily using the v9 image assistant to crop elliptically an image, and then the drawing tools to put a white disk in the middle, I turned this image: into the following one: that can be ...
943 views

### Creating a Logarithmic Scale Plot

I am trying to plot a function on a Log scale, but am not getting the correct looking output. Any ideas on what could be wrong. ...