0
votes
1answer
111 views

How to parse a .css file generated by Mathematica? modify values, add some values

How to parse a .css file generated by Mathematica (Export notebook to HTML)? modify values, add some values. convert into a expression? Are there some instances? I've wrote a simple function to ...
6
votes
2answers
590 views

Finding a 3d curve from torsion and curvature with NDSolve

I'm trying to use the Frenet–Serret formulas to find the curve that matches the torsion and curvature I specify numerically with an InterpolatingFunction. The ...
2
votes
2answers
131 views

Quadratic Equations mod p^k

As part of a larger program, I need to solve $A x^2+B x+C \equiv 0 \mod p^k$ for prime $p$. Right now I'm doing this by calling ...
0
votes
1answer
85 views

Subgraph, HighlightGraph not acting as expected

I'm trying to create a simple graph from a matrix and then highlight a particular subgraph. My code (simplified from a bigger task) is as follows. I keep getting the "Subgraph::graph: A graph object ...
12
votes
4answers
450 views

Elegant high precision `log1p`?

Sometimes it is hard to understand how numerical expressions are evaluated. I remember reading claims by Wolfram on how smart the Kernel is to evaluate expressions trees numerically by recognizing ...
1
vote
1answer
398 views

How to generate the truth table to prove logical equivalence?

How to generate the truth table to show that $p \implies (q \vee r)$ is equivalent to $(p \wedge \neg q ) \implies r$ ? Can I use BooleanTable?
0
votes
0answers
164 views

Alternate method of conjugation using replaceall

Mathematica really struggles to simplify complex conjugates of complicated expressions - even given assumptions for every symbol in the expression being real. Often times I've found that I can ...
1
vote
1answer
126 views

Module that finds the sum of digits of any given positive integer

How can I make a module that finds the sum of digits of any given positive integer? I use this command F[x_]:= Apply[ Plus, IntegerDigits[x] ] Is there another ...
13
votes
6answers
656 views

Elegantly split a matrix into positive and negative parts?

I have a matrix $M$ of real components, and I want to split it into two matrices $M^+$ and $M^-$ of the same dimensions as $M$, where $M^+$ contains the positive components of $M$ (the remaining ...
1
vote
0answers
180 views

No response from DSolve

Using optimal control theory, I am trying to find the optimal paths of d and k such that they will maximize profit as given by lc: ...
1
vote
0answers
144 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
62 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
777 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
132 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
104 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
189 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
115 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
157 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
150 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, ...
2
votes
3answers
365 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
203 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
35 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
277 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
230 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
124 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
199 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
194 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
147 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
164 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
55 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
161 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
86 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
252 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
134 views

Limit won't compute

Does anyone know why the limit: ...
0
votes
1answer
91 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
85 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
318 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
85 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
165 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
97 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
78 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
258 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
119 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
142 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
197 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
59 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
303 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
171 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
195 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\; ...

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