# All Questions

235 views

### String templating

I am pretty new to string processing in Mathematica. But I'm having some problems in doing simple string template filling to my mind elegantly. For example when doing export for my answer here, one of ...
856 views

### How can a power of 0 or 1 be replaced?

Consider this given example for ReplaceAll 1 + x^2 + x^4 /. x^p_ -> f[p] This returns ...
83 views

### How can I speed up the export of graphs in DIMACS format?

I'm creating random graphs with suitable properties and exporting them in the DIMACS format. Already, for rather small graphs with, say, ~60k vertices and ~240k edges, ...
104 views

### Factoring terms out of a polynomial

I don't do much algebra in Mathematica and was surprised to discover, while attempting to answer this question, that I had no idea how to factor out an expression from a polynomial. The question was, ...
160 views

### How to color separate a colored-in-pencil drawing?

I'd like to pick out just the "pencil" color in some drawings done by a young member of the household (he'd like to print out copies of these pictures and distribute them to his class mates on the ...
74 views

### Symbolic Output after numerical computation

I have a small question about the symbolic output. I started to write a program that generates the coordinates of n-dimensional polytopes by Wythoff construction. For crystallographic groups, all is ...
103 views

### How to use LineLegend and SwatchLegend together

I am wondering if one can place on the right of the plot frame a single legend that is a combination of a LineLegend and a SwatchLegend. What I want is to see the line with its label on top of the ...
683 views

### Is there a way to increase the smoothness of a cylinder?

I am using Cylinder to produce wide flat disks (in Mathematica 8). This works just fine except that the circular base of such a cylinder turns out to be really just ...
225 views

### More efficient Omnibus number determination?

Amusing myself with concepts from "Omnibus Sequences, Coupon Collection, and Missing Word Counts", in particular the sequences. To paraphrase the concept, a string is k-Omni over some alphabet a if ...
44 views

### How to joint symbolic expressions together [duplicate]

I want to joint symbolic expressions together to create a another symbolic expressions. one way to do that is as follows: ...
65 views

### A derivative encountered in matrix factorization using gradient descent

I want to factorize a matrix $a_{ij}$ as $$a_{ij} = \sum_k u_{ik} v_{jk}$$ using variational method for some reason. That is, I want to minimize the cost function $$F = \sum_{ij} b_{ij}^2$$ with ...
67 views

### Why does show combined plots and graphics fail in CDF Player but not in Mathematica?

The question is, how might I get the following script working as a CDF demo of complex inversion in a circle? It works fine in my home edition of MMA 8 run on OS X Mavericks. When saved as a CDF file ...
175 views

### Circumnavigating a curve or going through it to show different behavior

I am not sure if what I want to do is possible in Mathematica. I've provided something simple below to convey what I want to do. Basically what I want to happen is that when the ...
61 views

### Using Table with arbitrary number of variables [closed]

Let $P=\{p_1,...p_n\}$. I would like a way to implent Table[Expression,{$p_1$,lim},{$p_2$,lim},...,{$p_n$,lim}] where n and lim are parameters defined by the user. Any ideas?
60 views

### Finding the right DeleteCases pattern for <<199>>

I have a list in Mathematica with several items like <<199>> and <<104>>, I would like to get rid of them using DeleteCases, but none of the patterns I ...
101 views

### Comparison Operation for Nested Matrices

I have a nested matrix n as bellow ...
58 views

### After executing MessageDialog[] how can I wait for it to close before continuing

After executing MessageDialog[] how can I wait for it to close before continuing? I want to popup up a message and wait for the user to hit OK before continuing. Is there a mechanism for this?
222 views

### wolfram mathematica intersection of two surfaces [duplicate]

I use wolfram mathematica. There is a function of two variables which defines the surface z = f(x,y), the second surface is defined as z = const. How to find the line of intersection of these two ...
60 views

### Ploting fourier transform [closed]

I want to Find the fourier transform of this graph. {ListLinePlot[hari, PlotRange -> {{0, 200000}, {-1.5, 1.8}}]} And when I Put: ListLinePlot[Abs[Fourier[hari][[2 ;; 100]]], PlotRange -> All, ...
70 views

### Creating function with matrix argument

I am completely new to programming, so I apologize in advance for a stupid question. I want to program an algorithm for computing invariant factors of a finitely generated abelian group, so in ...
52 views

### Simple derivative not working [closed]

I'm a complete newbie to Mathematica. I've been using Wolfram Alpha Pro as well as MS Mathematics for a few months but wanted to dive into using a more powerful tool. I'm having a problem with ...
36 views

### NIntegrate Issue: Changing integration limits makes calculation time extremely long

After a long time developing some code in mathematica and finally getting it to work, I have unfortunately encountered an odd problem: When I change the limits of integration (and shift the function ...
233 views

### Defining a pure function involving a function argument

I've got an expression involving x and y that I want to use as a MeshFunction: ...
25 views

### Why I am not getting the same frequency when sampling a waveform? [duplicate]

I am trying to simulate the sampling of a waveform to then apply FFT Analysis to it. Here is the sample code I have now using a square wave: ...
68 views

### Smooth out contour in RegionPlot/ContourPlot

I would like to smooth out the jagged edges in the outermost contours in the following plot: I have data of values as a function of variables (x,y) in the form ...
184 views

### Exponential of a Differential Operator

In Mathematica, is it possible to exponentiate a differential operator such that the operator will act on a function, $f(x,p)$? Specifically, I wondering if I can get Mathematica to do this: ...
763 views

### A question regarding 1 divided 243

Here is a problem due to Feynman. If you take 1 divided by 243 you get 0.004115226337 .... It goes a little cockeyed after 559 when you're carrying out the decimal expansion, but it soon straightens ...
69 views

### Laplacian in D Dimensions

Is it possible to compute $\Delta F=\nabla^2 F$ for $F=F(x^1,x^2,…,x^D)$ with $D$ finite? I seem to be only able to specify spherical coorindates, for example, if I want to leave standard ...
80 views

### Drop row if sum of part of row is equal to zero

My problem is the following: Suppose I have a matrix A which looks the following: ...
78 views

### How to force Manipulate to use preserve control settings over successive evaluations

I have this Manipulate: Manipulate[Plot[Sin[a x], {x, 0, 2 Pi}], {a, 0, 3}] Now, I realize I had mistyped the expression and it's actually ...
858 views

### Fitting points to tilted, off-center ellipse

I have 24 x-y points that are supposed to form an ellipse. ...
70 views

### Can Array work as Loop? [closed]

I got Mathematica code from my friend: ...
141 views

### Rotation matrix $\to$ quaternion

I found a very good link about quaternions in Mathematica , but I don't know how to create a quaternion from a rotation matrix. Can anyone help me, please? Update I need this: A rotation may be ...
75 views

### Strange numerical integration result

I write a function called berrycur[kx,ky] which I will give at the end of the question, and want to numerically integrate this function over {kx, -2π, 2π]}, {ky, 0, ...
99 views

### github api v3 repository create

I'm trying to create a github repository form a notebook, using this simple code ...
59 views

### Any command for group products?

Is there any Mathematica command or well known technique to take the direct product between two symmetric/permutation groups?
96 views

### I cannot get tables names and columns names from database

I am working with database using OpenSQLConnection-JDBC. I am able to fetch the data perfectly from the tables but I cannot get nor the names of the tables (using SQLTableNames) neither the column ...
144 views

### Error message: Coordinate index 0 is out of range for the enclosing GraphicsComplex

I am unable understand following error message: Coordinate index 0 is out of range for the enclosing GraphicsComplex. How to fix it? Attached data here: pts and polygons. See also end of question. ...
705 views

### How can I add a column into a existing Dataset?

I'm very excited about the brand new Dataset function. I have played with it in Wolfram Cloud, and haven't figured out how can I add a new column into an existing ...
31 views

### Adding various combinations of rational expressions [closed]

as a newbie to Mathematica I wonder if someone can help... I'm generating a puzzle worksheet for some students and wish to add linear rational expressions, three at a time from a pool of six. e.g. ...
188 views

### Alternatives ordering affects pattern matching in Cases?

Given expr = f[x, g[y], z] In the following query, the pattern h_[__, c_] appears as last slot in ...
134 views

### Trying to model Heat flow trough different materials with NDsolve

What I'm trying to achieve is model of the heat flow, in this case for the simplest 1D case,its relatively easy to do for the steady state case, but when I try to do it with NDsolve so I get the ...
42 views

### How do I constrain the result of fitting my non-linear model to be greater then 0

fitresulty21 = NonlinearModelFit[ydata21, {funfit[y, σ, A, B, x1, d, d/2], A > 0}, {{x1, 20}, {σ, 3}, {A, 200}, {B, 2000}, {d, 110}}, y]; ...
137 views

### Solve works with numbers but not number stored in variable

I have the code: ...
103 views

### Symbolic evaluation of the sum of KroneckerDelta

I want to evaluate this simple expression $$\sum_n f(n)\delta_{mn} = f(m)$$ using this: Sum[KroneckerDelta[m, n] f[n], {n, Infinity}] However Mathematica ...
247 views

### How do I save/export a list so that it can later be easily imported as a list again?

I have a couple of big lists (each of them contains elements that are themselves lists of two elements, i.e. an element of each list that I have is of the form {x, y}) that I want to save/export. ...
124 views

### Adjusting the vertices positions of a RandomGraph

By adopting the codes I got from the previous questions, here I intend to adjust the vertices positions of a RandomGraph. However, I only got an inactive graph, it even disappears suddenly when ...
52 views

### How do I estimate the Pareto front in my multiobjective optimization problem?

I need to minimize a function of two parameters that gives two "stress" outputs {A,B} = f[tau,mu]. How do I estimate (even roughly), the Pareto front for this ...