1
vote
0answers
146 views

Failure of CountryData due to connectivity?

Today I started researching the "Four colours theorem" and to do so I need data, regions for example. I tried using the following line: ...
0
votes
0answers
63 views

Define new 3D graphics primitives in Mathematica 9 [duplicate]

I have generated a three-dimensional probability distribution function (PDF) and I would like to place a series of these PDFs at certain coordinates on a cuboid. I've rasterized the PDF so it is a 3D ...
2
votes
1answer
846 views

Calculate mean square displacements for different particles from a excel file

I have the particle movement data in the following format: ...
7
votes
3answers
139 views

Disable rounding up of PolarAxesOrigin

How to disable rounding up the radius which is used to calculate the origin of the polar axes with the option PolarAxesOrigin? Example: ...
1
vote
1answer
111 views

Is it possible to create a output cell without generating a cell tag from the input cell

I give a CellTag to my Input Cell, but the output cell would also inherit the CellTag. Is it possible to control not inherit the CellTag? Sometimes I need the output cell with the CellTag, but ...
1
vote
1answer
206 views

Perform FindRoots on Function Evaluation Containing RootSearch

I am using Ted Ersek's RootSearch function in Mathematica 9.0 (http://library.wolfram.com/infocenter/Demos/4482/) to create a function that I am using for graphing. ...
1
vote
1answer
125 views

Transform list of inequalities into matrix form $A\ x \leq b$

I have a list of linear inequalities, and I want to get it into the form $A\ x \leq b$; i.e., find the matrix $A$ and the vector $b$. Is there any function in Mathematica that can that can do this?
0
votes
1answer
160 views

How to use ParametricPlot Wih Conditions (or similar)

I´m analizyng the game "Battle of the Buddies" similar to "Prisioner´s Dilenma" All works fine, BUT... I want to draw in red the point whose coordinates are less than the coords of a strategy. ...
2
votes
3answers
158 views

How to do subtraction with sets in which the elements have multiplicity indicators? [duplicate]

I want to do subtraction with sets l1 and l2, which contain multiplicity indicators. For example, ...
3
votes
3answers
406 views

Extracting coefficients from g=a*x+b*y+c*x*y

I have a Response Surface Equation (RSE) that I'm trying to extract coefficients from. It has a form similar to: g = a*x + b*y + c*x*y; I want to be able to ...
1
vote
3answers
210 views

Table iteration over two ranges

I am trying to create a Table where the iterator has two ranges with different iteration steps. Let's consider a simple example: I want to find the square of the ...
2
votes
0answers
40 views

The value of PageWidth doesn't work for saving as HTML?

CellPrint@Cell["Test","Text",PageWidth->300,Background->Red] And I got this snippet of HTML code: ...
4
votes
2answers
300 views

How to add the pause button to that dynamic stopwatch?

Referring to How to make a dynamic stopwatch? Timers can now be created with timer = makeTimer[] and utilised with actions such as ...
2
votes
1answer
244 views

Return “true” if point is in Convex Hull [duplicate]

I have a set of points Z: Z = {{x1,y1},{x2,y2},..,} I would like to obtain a function that returns ...
0
votes
0answers
43 views

Limits of PrimeNu [duplicate]

Is there any way to find distinct prime factors for very large numbers using Prime and/or PrimePi that exceeds the ...
3
votes
2answers
133 views

Keep data in memory inside a notebook without having to evaluate it again [duplicate]

I have a notebook that calculates some data in a relatively large time so I want to keep these data saved inside the notebook without recalculate them every time I open the notebook. I know I can ...
0
votes
3answers
207 views

Determinant of a random matrix consisting of integers

I am trying to implement a function that finds the determinant of a random matrix consisting of integers. This is the code I have written so far, but I am stuck. Suggestions ? I want to find a ...
2
votes
1answer
199 views

Flipping x-tick-labels on custom plot

I'm slightly new to the world of Mathematica, so I can't assess the difficulty of my request, but anyhow, this is my question: I have 2 datasets that I want to plot with two y axes, and a reversed x ...
3
votes
0answers
151 views

Do a gauge transformation for a Chern-Simons theory?

Suppose we have the following Lagrangian density: $$ L=\epsilon^{\mu\nu\rho}\big(\sum_a A^a_{\mu}(x) \partial_\nu A^a_{\rho}(x)-\sum_{a,b,c}\frac{1}{3} f^{bca} A^a_{\mu}(x) A^b_{\nu}(x) ...
6
votes
3answers
171 views

Multiplication sign in TeXForm?

How do I get Mathematica to produce TeX output that does not omit the multiplication signs ? For example, this expression: ...
0
votes
2answers
56 views

Numeric output formats

I want to print the expression $A[x] = 8020.6596 \times 1.055^x$ as is on a 2D graphic. I included the line ...
9
votes
1answer
168 views

How to avoid CopyTensor in CompiledFunctions?

In a reply here Leonid wrote, “Compile can handle a number of higher-level functions, such as Transpose, Partition, Map, MapThread, etc. Most of these functions return expressions, and even though ...
0
votes
3answers
87 views

Preventing evaluation until all undefined symbols are resolved

FixedPoint[If[# <= 0, 0, # - 1]&, 2 x] Causes an infinite loop because of 'x'. How do i automatically prevent evaluation until ...
1
vote
1answer
270 views

Part::pspec error returned when using a ListLinePlot ColorFunction variable as list index

In ListLinePlot, I'm attempting to construct my own ColorFunction for coloring points differently based on a third dimension of data not plotted to a specific axis. However, ColorFunction only uses ...
4
votes
2answers
139 views

Limit won't compute

Does anyone know why the limit: ...
0
votes
1answer
94 views

How can a function with an embedded function be compiled?

Compile fun continues today, and I'm trying to get the function below to compile. First the function: ...
2
votes
2answers
89 views

`PrimeNu` counting function

Building on this question, what is the most efficient counting function for distinct prime factors? It would obviously be more efficient if Prime and ...
6
votes
1answer
347 views

Maple like collect command in Mathematica

In Maple I often simplify expressions for functions of same argument using the collect command: > collect(a*f(x)+f(y)+x*f(x), f, factor) (a+x)*f(x)+f(y) where ...
1
vote
1answer
86 views

Asymptotics of sum of binomials

I would like to find the asymptotics of Sum[Binomial[n,i]*1/i^((n+1)/2),{i,1,n}] I saw Find asymptotics of Sum[2^i*Binomial[n-i-1,2*n/3-1],{i,0,n/3}] but I ...
1
vote
1answer
170 views

Problem to solve an integral equation [closed]

I am new to Mathematica. I am trying to numerically solve for C in the following equation: $\begin{equation} \begin{array}{lcl} -\int_0^\infty (5000000+100000 x+ C)^{-1} ...
1
vote
2answers
99 views

Identify / change working directory for the InstallableNET runtime

I am currently attempting to use .NET/link to call a third party DLL from Mathematica using DLLDefinedFunction. I have been able to link against and call many of ...
3
votes
0answers
97 views

Understanding NDSolve::ndsz

I'm working on a largeish system of differential equations where I encounter the NDSolve::ndsz step size is effectively zero; singularity or stiff system suspected ...
6
votes
3answers
260 views

Loop function over list [duplicate]

I would like to divide element 1 of a list by element 2; element 2 by element 3, and so on. What is the best way of doing this? I have tried f = #1/#2 & ...
2
votes
1answer
125 views

Solving Complex Equation Over Reals

I want to solve the equation $\frac{abi}{a+bi}=4-2i$, where $a$ and $b$ are real numbers. I know from hand-solving the answer is $a=5$, $b=-10$. How do I get Mathematica to tell me this? I tried: ...
4
votes
1answer
148 views

Exporting images in a Mathematica array to a PDF s.t. each image is precisely $n \times m$ millimeter in dimension [duplicate]

I have a number of images in a Mathematica array, and I'd like to export the images to a PDF s.t. each image is precisely scaled to be $n \times m$ millimeters in dimension. The idea is that printing ...
4
votes
2answers
200 views

Is it possible to `Protect` a dynamic programming process?

I wrote a function using dynamic programming to speed up the evaluation. For safety, I also want to protect this function. Take factorial for example: ...
1
vote
1answer
61 views

How to get the time when a notebook is saved and closed

I want to get the time when a notebook is created and the time when the notebook is saved and closed, that is to say, the whole time when a notebook exist. What should I do? Thank you!
2
votes
1answer
325 views

Resonance Curve using NDSolve

I am trying to make a resonance curve like this one below, using NDSolve. I tried to use code as below. Basically I try to hold solution for a w (driving frequency value) using NumericQ and then ...
4
votes
1answer
192 views

How to get an equivalent of WeightedData in Mathematica 8?

Is there an equivalent command of WeightedData (new in version 9) in Mathematica 8 or I have to define it by myself? I haven't found anything in the site or ...
5
votes
0answers
203 views

Units: Custom-defined units possible?

Converting between revolutions per minute (RPM) and revolutions per second (RPS) is not straightforward for me in Mathematica. I know that $1\; \text{RPM} = \frac{2\; \times\; \Pi\; ...
0
votes
0answers
245 views

Solving for equilibrium distribution (symbolic) by matrix multiplication

I have a huge transition matrix (81x81). The matrix is too huge to paste here, so I store it in this notebook. (There are constraints on the symbols: $0<p_b<1$ and $0<p_g<1$. If further ...
23
votes
4answers
3k views

How to create effect like Van Gogh's stroke brush?

I need to apply Van Gogh's stroke brush effect to a random image Take the following image as an example: Thank you so much if you could help!
0
votes
0answers
136 views

Making a predictive statistical model

I am totally new to Mathematica, and I have never used a similar program, apart from perhaps Excel (and I didn't even use Excel on a professional level). So I want to create a mathematical model ...
1
vote
1answer
177 views

How should I go about writing more functional and list based code? [duplicate]

I've heard that Mathematica is usually faster when the code is list-based and/or uses a functional paradigm. I'm still working on getting the hang of this; there are a lot of ...
1
vote
1answer
202 views

How do I construct a non-linear model from experimental data?

I want to find a function $w=f(x,y,z)$ that fits experimentally determined values of w. For example, assume ...
2
votes
2answers
131 views

Deleting elements on a list by the first element of another list

I was trying to make this L1 = {{2, 1}, {6, 4}, {8, 7}, {9, 5}}; L2 = {{2, 9}, {9, 6}}; L = Union[L2 , L1] And I used this: ...
1
vote
1answer
74 views

Defining functions that reference other values

How could I define a function that references other values? eg a = 2 x; b = 4 k; f[k_, x_] := a^b
0
votes
1answer
213 views

Is it possible to convert expressions containing Root objects to Excel formulas?

I am still a beginner and do not fully understand pure functions and root objects. When I tried to calculate the inverse of a function, Mathematica gave me: ...
5
votes
0answers
1k views

Threads vs Cores: How many kernels need to launch in parallel Mathematica?

I have a dual-core intel machine. I would like to test how many parallel local kernels should be launch to get the optimized performance. Knowing that the HyperThreading technology of Intel could run ...
2
votes
1answer
82 views

Need to run evaluation 2 times

Why does this only work after running the evaluation 2 times? ...

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