3
votes
3answers
162 views

Smooth initial data

I need something that produce pseudorandom smooth initial data for modelling phase separation equations (Cahn-Hilliard and simular). Generator code for now: ...
1
vote
1answer
39 views

How to print TeXForm running script?

I've got a simple script which runs in bash some code - I want now to get an answer in TeX Form. If I would run Mathematica code inside the interpreter, it would be easy: ...
5
votes
2answers
101 views

How can DateObject handle calender weeks

I have dates given for a TimeLinePlot. These dates are in {year,week} format. DateObject ...
-4
votes
1answer
50 views
5
votes
1answer
81 views

Two dimensional recurrence

My actual problem is a bit more complicated, but let us first assume that we have a recurrence relation of the following type $a_{n,l} = a_{n-1,l} + a_{n-1,l-1} + a_{n,l-1}$ The boundary is given, ...
2
votes
2answers
239 views

Simultaneous equations—classify the solution set as finite, infinite, or none [duplicate]

How do I find the values of $b$ and $c$ for the equations $x + 5 y = 4$ and $2 x + by = c$ with a unique solution, an infinite set of solutions and no solutions with Mathematica?
3
votes
0answers
74 views

Playing a sound gives errors in Mathematica 10.3

I tried this Play[Sin[2 Pi 440 t], {t, 0, 1}] and it gives errors. What is wrong with my Mathematica( v10.3)? Update I found what cause this warning ...
20
votes
3answers
607 views

Detecting components in timeseries

I'm looking at this sequence of values: I'd like to detect the points where the center of the time-series shifts (around x=1000 and x=2000). Many of the transforms and smoothing methods I have ...
1
vote
2answers
79 views

How can I eliminate a parameter by substitution and simplification?

I have this equation k = (a b c t)/(Sqrt[(f + t)^2]) and I want to set p = t/(t + f) In which way I can eliminate ...
6
votes
1answer
178 views

NDEigensystem producing imaginary eigenfrequencies for the vibrations of a cantilever [closed]

We are trying to use NDEigensystem to solve for the vibrational modes of a cantilever with triangular cross-section. However, many of the solutions provided by NDEigensystem have imaginary ...
2
votes
2answers
73 views

Rewriting the set of equations in terms of new variables, using replacement rules when the expression contains partial derivatives [duplicate]

I am working with cumbersome equations, that contain a lot of terms. Here I will consider simple example: ...
3
votes
1answer
88 views

Is there a simple way to get the Conjugate of a complex term, provided all information is available?

I've found a few threads addressing this, but they all seem to have pretty clunky answers, and it's hard to believe there's not a more elegant solution in Mathematica: Remove annoying Conjugate a ...
2
votes
2answers
113 views

Implementing an affine cipher

I am trying to create functions for encoding and decoding an affine cipher in Mathematica. I have written these two functions: ...
3
votes
1answer
108 views

How can I find the coefficients of the next recursive symbolic function?

I have the following function $$ f(x+3k) = -mf(x+2k)+f(x) $$. If we get $x=x+k$, then $$ f(x+4k) = -mf(x+3k)+f(x+k) = m^2f(x+2k)+f(x+k)-mf(x) $$. Also we obtain the coefficients of the final functions,...
2
votes
3answers
81 views

How to set/adjust Precision for an iterative calculation?

How should I restructure this code? I generate a high-order polynomial poly with integer coefficients, then find roots and divide them out of poly one at a time. ...
8
votes
1answer
102 views

Duplicate-free results of permutations + constant list

Given a constant list const, e.g. const = {-(15/2), -(13/2), -(17/2), -(15/2), -(13/2), -(11/2)} of length ...
3
votes
0answers
32 views

How to identify the program that is running my notebook or CDF file [duplicate]

Is there a way to programatically know which Wolfram product is evaluating a notebook or cdf file: Mathematica, CDF Player, or CDF Player Pro, Wolfram Cloud? I'm currently using $InstallationDirectory ...
1
vote
1answer
119 views

What is the fundamental difference between “PlotPoints” and “MaxRecursion”?

When making a plot, PlotPoints or MaxRecursion options are used to specify the accuracy or the extent of how detailed the result will be. Ff either of them do the similar job, I think ...
2
votes
1answer
73 views

VertexLabels with Graph Properties

Suppose I have a graph like this Graph[ {1 <-> 2, 2 <-> 3, Labeled[3 <-> 1, "hello"]}, VertexLabels -> Placed["Name",StatusArea] ] Now ...
2
votes
2answers
150 views

HIghlight intersection of two disks [duplicate]

I tried this: reg1 = Disk[{0, 0}, 1]; reg2 = Disk[{1, 0}, 1]; reg3 = RegionIntersection[reg1, reg2]; Then this: ...
1
vote
1answer
128 views

Controlling plot range of histogram

I tried the following code: ...
0
votes
1answer
48 views

How to define InterpolatingFunction on a variable set of points?

I would like to define an InterpolatingFunction to which data points are transferred as a parameter, e.g.: ...
4
votes
1answer
54 views

Clues on theorem proving tools?

I'm trying to prove $[a \cup (b \cap c ) = (a\cup b)\cap (a\cup c)]$ with mathematica. But I don't know what function I should use. I've rewritten the sentence in the following way: ...
1
vote
2answers
51 views

change the output of Print command in Article style

I am working with the Article-style. How can I change globally the output of Print command? For example typing ...
0
votes
0answers
42 views

Multiple numerical integrations and green's functions propagation of the solution

I have to solve a system of equations where the coefficients have to be computed from numerical integrations. My problem is that my codes is to extremely slow because I each time that it has to ...
2
votes
0answers
92 views

Convert (rescale) 16 Bit png image

I have a camera (12 Bit Sensor, 2048 * 2048 Pixels). The images can also be exported in 16 Bit png format. Here different settings can be used. One setting is somewhat strange. For this special case ...
4
votes
4answers
228 views

Another confusion with simplify

After reading some of the questions concerning Simplify, I still didn't find a solution to my confusion. I want Mathematica to simplify ...
3
votes
1answer
65 views

Generate list of traceable and planar graphs

Is there any way to tell Mathematica to generate a list of graphs that are both traceable and planar?
5
votes
2answers
132 views
1
vote
1answer
64 views

How to add color to listplot

I have generated many points in a 2-dimensional space (x,y). How do I use color to represent different values of f(x,y) in ListPlot? Does ...
2
votes
2answers
133 views

A simple question: Input problem

I have a simple problem. First I define the value of variables, then I calculate the expression as the following: Code 1: ...
16
votes
1answer
373 views

Creating a cloud of blocks that form I ♥ U in different viewpoints

This picture shown bellow has three shapes with different view angle (I ♥ U). How to do this type of model? A few tries: ...
3
votes
1answer
89 views

Author Tools layout for a table of contents

Can someone point me at the place, where the Layout of the Table of Contents is stored in the Author Tools. There should be some style sheet, but I can't find it. Author Tools is still a very useful ...
0
votes
2answers
116 views

Referencing elements of ArrayRules

How do I call elements of ArrayRules by their indices rather than by Part[ArrayRules[list],i]? I'd like to call the element that ...
0
votes
1answer
35 views

What is the function “oneflag_:0” in this expression? [closed]

The first function Pivotdown can zero out all entries in a column below a desired location. But l don't know the function of “oneflag _0".
8
votes
1answer
75 views

Why does the front-end no longer like MixedRadix as an argument for UnitConvert?

I often find MixedRadix very useful for make certain kinds of unit conversions. For example, ...
4
votes
1answer
30 views

List of sound objects indexing

I am creating a list of sound objects: tones={}; For[j = 0, j <= 40, j++, tones = Append[tones, Play[Sin[2*Pi*t*500/Exp[-0.1*j/20]], {t, 0, 1}]]]; Each ...
1
vote
2answers
49 views

Style changes for a moment when parameters change [closed]

I've been looking for a solution to this problem for other applications too, for some time, but haven't come up with a solution that does not involve Animate or ...
3
votes
1answer
50 views

Replacing elements of a matrix

I'm trying to write a program that takes a given matrix $A$ of 1's and 0's and flips a designated amount of 1's to -1's. ...
1
vote
1answer
61 views

Generate a simulated covariance matrix

I am working on a problem where one of the input variables is the level of covariance between the entries in a particular matrix. To simulate this problem in Mathematica, I will need to feed my code ...
6
votes
1answer
107 views

Continuously varying tube radius

I'm currently trying to draw tubular neighborhoods of torus knots, which Mathematica's "Tube" function allows me to do quite easily. My question regards the appearance of the neighborhood: Is there ...
3
votes
2answers
69 views

Assigning multiple solutions different replacement names

Let's say we are solving a homogeneous differential equation, such as $$y^{\prime\prime} + a y^{\prime} + b y = 0$$ with characteristic equation $$s^2 + a s+ b = 0.$$ Using the ...
0
votes
1answer
43 views

Why does this ContourPlot3D not give the result I expect? [closed]

ContourPlot3D[(mod[x, 10]-5)^2 + y ^2+z ^2 ==1, {x, -20, 20}, {y, -20, 20}, {z, -20, 20}] shows blank rather than the array of balls I expect. Why?
0
votes
1answer
70 views

How to define where a line intersects its reflection

It is relatively easy to be able to find where two parametric functions intersect each other, but how about when one is a function and the second is its reflection? In the example below is it possible ...
9
votes
2answers
180 views

Position with test for list of lists [duplicate]

Why do I get this error message? It seems to me that the level specification should have done the job. ...
0
votes
0answers
51 views

Avoiding the “CloudObject`Private” context bug in controls of embedded Manipulates

I have Manipulates that I develop in one notebook and then paste in another. This second notebook is meant for a presentation, and shouldn't have these odd ...
5
votes
1answer
78 views

Display position of expression as Tooltip

How could we display the position of any sub expression in an expression using Tooltip? This would be useful for example in order to locate the position of an ...
0
votes
2answers
92 views

Weighted arithmetic mean [closed]

How can I calculate the mean value of my graphs computed below ...
39
votes
9answers
2k views

What would you ask Mathematica to do on a big system?

Our hardware supplier has given us the opportunity to test Mathematica on a big Windows system. The specs will be 1 to 4 TB of working memory and 12 sockets with 18 cores each. I got 1 full week of ...
4
votes
1answer
62 views

Computing the logarithmic spectral norm rapidly

I wish to compute the logarithmic spectral norm of a square matrix $A$, which is defined by \begin{equation} \mu_2[A]=\lim_{t\downarrow0}\frac{\|I+tA\|_2-1}{t}. \end{equation} Hence, I simply code ...

15 30 50 per page