# All Questions

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: ...
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: ...
101 views

### How can DateObject handle calender weeks

I have dates given for a TimeLinePlot. These dates are in {year,week} format. DateObject ...
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### 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, ...
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?
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### 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 ...
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 ...
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### 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 ...
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 ...
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### 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: ...
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### 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 ...
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: ...
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,...
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### 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. ...
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### 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 ...
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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 $InstallationDirectory ... 1answer 119 views ### What is the fundamental difference between “PlotPoints” and “MaxRecursion”? When making a plot, PlotPoints or MaxRecursion options are used to specify the accuracy or the extent of how detailed the result will be. Ff either of them do the similar job, I think ... 1answer 73 views ### VertexLabels with Graph Properties Suppose I have a graph like this Graph[ {1 <-> 2, 2 <-> 3, Labeled[3 <-> 1, "hello"]}, VertexLabels -> Placed["Name",StatusArea] ] Now ... 2answers 150 views ### HIghlight intersection of two disks [duplicate] I tried this: reg1 = Disk[{0, 0}, 1]; reg2 = Disk[{1, 0}, 1]; reg3 = RegionIntersection[reg1, reg2]; Then this: ... 1answer 128 views ### Controlling plot range of histogram I tried the following code: ... 1answer 48 views ### How to define InterpolatingFunction on a variable set of points? I would like to define an InterpolatingFunction to which data points are transferred as a parameter, e.g.: ... 1answer 54 views ### Clues on theorem proving tools? I'm trying to prove$[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: ... 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 ... 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 ... 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 ... 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 ... 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? 2answers 132 views ### How to get rid of the mesh of a MeshRegion in a same pane ... 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 ... 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: ... 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: ... 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 ... 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 ... 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". 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, ... 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 ... 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 ... 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. ... 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 ... 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 ... 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 ... 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? 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 ... 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. ... 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 ... 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 ... 2answers 92 views ### Weighted arithmetic mean [closed] How can I calculate the mean value of my graphs computed below ... 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 ... 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 $$\mu_2[A]=\lim_{t\downarrow0}\frac{\|I+tA\|_2-1}{t}.$$ Hence, I simply code ...

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