4
votes
0answers
89 views

Transform an expression to remove the singularity

I have the expression Sin[c x]/c. Clearly it is undefined at $c=0$, but that is merely a removable singularity, since $$\frac{\sin(cx)}c=x\frac{\sin(cx)}{cx}= ...
1
vote
1answer
109 views

Behaviour of Simplify when used with ArcTan and ComplexExpand along with assumptions

I am trying to simplify the slope of vectors with symbolic coordinates {x,y} using ArcTan[x,y] I am working with real X and Y I tried the following : ...
0
votes
0answers
31 views

FindRoot gives strange results when used on an interpolating function with vector output [duplicate]

I am currently experiencing a problem when I try to use FindRoot with an interpolating function that outputs a vector. I have constructed a minimal example that ...
0
votes
0answers
22 views

Question about a ParametricPlot with a shading grey family of lines and/or different sizes [duplicate]

So, I have this function of the polar angle $\theta$, with a varying parameter $t$: {Cos[\[Theta]] (1 + Sin[t]), Sin[\[Theta]]} and I want to draw it in a ...
5
votes
1answer
159 views

Parallel evaluation of Image and Rasterize problem

The following command: ParallelTable[Image[Graphics[{{Red, Disk[{5, 5}, 4]}}]], {i, 10}] shows a very strange behaviour. It starts a new Mathematica process on ...
0
votes
0answers
311 views

How to apply Robin boundary condition in Mathematica

Robin condition is the boundary condition which combines the Dirichlet and Neumann condition at the same boundary. For example: At the boundary x = 0 to 2: I want to apply ...
1
vote
1answer
181 views

What is most efficient way to convert system of equations to collection of functions?

I have the type of system M.x = b, where M is a known matrix and b is a known vector. M contains many parameters, call the entire parameter set 'a', so M => M[a]. I want to be able to efficiently ...
8
votes
0answers
115 views

What are the possible security breaches in CDF content?

It has been noted on this site before that the free CDF player is notoriously trigger-happy in declaring dynamic content to be "potentially unsafe", and forcing the user to enable dynamic content ...
2
votes
0answers
42 views

Differences in SetDelayed (:=) in Module and DynamicModule [duplicate]

I have a question about the differences in SetDelayed assignment functions in a Module and in a ...
8
votes
2answers
849 views

detecting the radius of an incomplete circle

I need your help to detect the radius of the blue circle in images like this: . Reading these questions: 1, 2, 3, I figured that this code taken from @halirutan answer to question n°3 could help: ...
1
vote
0answers
116 views

(Symbolic) LinearSolve is slower/different after upgrading to Mathematica 9

Yesterday I upgraded from mathematica 8.0.4.0 to 9.0.1.0. Trying to run the same notebook I used many times before, it takes ages to evaluate a symbolic (linearsolve) expression which before was ...
3
votes
1answer
187 views

Simplify equations with pattern assumptions

When simplifying an expression using Simplify[expr, assumptions], the assumptions has to be explicit. Is it possible to simplify an expression with pattern ...
8
votes
3answers
358 views

Deleting quasi-duplicates from large list efficiently

I have the need to remove "duplicates" from large (>10K members) lists, where a "duplicate" is either a verbatim duplication, or the element's second entry exists as a first entry for some "earlier" ...
-1
votes
1answer
99 views

Make Quantity behave reasonable with Degrees Celsius

When using a Quantity with the unit of "DegreesCelsius" multiplication doesn't work as expected. If you have 10 degrees and ...
6
votes
2answers
213 views

Generated Numbers under a constraint?

Let's say I have five four dimensional vectors $p_i^\mu=(p_i^1,p_i^2,p_i^3,p_i^4)$ with $i=1,2,3,4,5$. Now, I want to fill the entries of these vectors ($4\cdot5=20$ in total) with some numbers, but ...
1
vote
1answer
147 views

Image partition according to contours

I want to extract contours from following image or I am wondering how to partition following image: line image looks like: This question is linked: How to superimpose contour lines on ...
7
votes
3answers
211 views

Formatting an equation on a plot

I am trying to label a plot with an equation. The problem is that Mathematica formats things almost well but not exactly. The parenthesis are of the wrong size, and the powers are not high enough. ...
3
votes
1answer
56 views

Assign the Background rule in Grid (the positions can be described by a integer function)

For example, this code Grid[Transpose[Table[{n, n^2}, {n, 1, 10}]], Frame -> All, Background -> {{1 -> Red, 4 -> Red, 9 -> Red}}] produces , in ...
22
votes
4answers
781 views

Implementing a Beeswarm plot in Mathematica

I am looking for a Beeswarm plot implementation in Mathematica. Consider the following data: ...
3
votes
3answers
276 views

How to do Cases with multiple related patterns?

I would like to write a function similar to Cases, but can search for a group of related patterns together. For example, ...
4
votes
2answers
177 views

HTMLEncode a string for webMathematica

Is there a native Mathematica way to convert a string like "<select></select>" into ...
2
votes
3answers
148 views

Plotting lists, exact color values

I read some descriptions of similar problems but I cannot make them work in my example, I don't know why. I have list of 3 dim values to plot: x, ...
1
vote
1answer
96 views

Defining a function with global parameters

What I would like to do in Mathematica is something like f[x_] := a x g[a_] := NIntegrate[f[x], {x, 0, 1}] But then of course I get ...
2
votes
1answer
73 views

How to use Select to exclude a single element which I can control? [duplicate]

I have code which inserts an expression into lists that I need to remove. I can insert anything I want, a string, variable, or number, into the lists. Suppose I insert the number 13 as my blacklisted ...
4
votes
1answer
166 views

Mathematica rule to express exponentials as multiplication

I'm sorry if this has been asked before, but it is a very simple question and I would imagine it shouldn't be terribly hard for someone that knows to answer. I'm essentially trying to tell ...
1
vote
0answers
94 views

DifferentialEvolution scaling factor randomization

Using NMinimize for finding global minima, one can choose the DifferentialEvolution method. You can find a (not so) detailed ...
3
votes
2answers
266 views

How to superimpose contour lines on transformed image

My goal is to superimpose contours lines or contour plots on distance transformed image.
0
votes
1answer
84 views

Create jacobian Function from a vector Function

This is related to this question and maybe this question. I wanted a function that takes an n-parameter vector function and outputs a Jacobian matrix function, also n-parameter. I think this works: ...
2
votes
2answers
123 views

Merge two Matrices without Duplicates

I have two matrices, for example: data1 = {{"c1", "c2", "c3"}, {2, 5, 3}, {54, 2, 3}, {11, 2, 10}, {3, 5, 7}}; and ...
5
votes
1answer
138 views

Solving an identity

I am trying to solve this identity using Mathematica: $$3 \sqrt{5 \sqrt[3]{37}-16}=\sqrt[3]{a}-\sqrt[3]{b}-c $$ I know that a, ...
1
vote
0answers
102 views

New list generated from the sum of elements taken from two lists

I have been using mathematica for a while, but I have problem wrapping my head around list manipulation functions. I would appreciate any suggestions. Here is what I want to do. ListV is a list of ...
0
votes
0answers
99 views

Can this function be numerically integrated

I need to integrate the function, $f(a,b)=-g(a,b)ln(g(a,b)) = -1/ Pi(( (E^(-((a^2 - E^(-t [Gamma]) [Alpha]^2)/( 1 + 2 [Sigma]^2)))) [Pi] ([Sigma]^2) )/((1 + 2 [Sigma]^2) (E^(2 ...
5
votes
0answers
511 views

Estimate parameters of the state space model

I'm using Mathematica 9 and its Control Systems functionality. I've searched the references extensively but seem not to be able to find any examples of state space model parameters estimation. All ...
2
votes
3answers
3k views

Install issue: Mathematica 9 on Ubuntu 13.10

I am trying to install Mathematica 9 on a Ubuntu 13.10 system. I had this working on my previous 13.04 version but now it breaks on when trying to unpack the sh archive: ...
1
vote
0answers
151 views

Calculating derivatives of roots of equation

I am interested in calculating how the roots of an equation change as one of the variables does, when the equation is evaluated numerically rather than symbolically. I have edited this code to be ...
1
vote
1answer
238 views

{Latitude, Longitude} to Transverse Mercator projection

I have a shapefile with the following "CoordinateSystemInformation": ...
9
votes
1answer
109 views

Why does $Failed have attribute HoldAll?

Why does $Failed have attribute HoldAll? Are there typical situations where $Failed is ...
3
votes
2answers
181 views

Change ticks from number to hours

I have an unidimensional array (let's call it list)ranging from 0 to 86400, each one representing a second of a day (a day has 86400 secs). For example, ...
2
votes
2answers
115 views

DynamicModule with intermediate expressions

I am trying to generalize a Manipulate construct into a DynamicModule one to try and include smoother controls, but I seem to be ...
8
votes
1answer
309 views

Export an image at 1000 dpi

I'm trying to export an image at 1000 dpi. The author guide of a lot of papers wants this resolution! Then I must to import this image in Word in a small box; let's say 7x4 cm. This is the code that I ...
4
votes
0answers
124 views

Can Mathematica Operators be combined in a linear fashion for readability?

Here's a simple example. Suppose we want to find the off-diagonal matrix of m: m={{1,2},{3,4}} This can be solved fairly simply by extracting a list of the ...
3
votes
1answer
382 views

N[number, 100] does not give 100 decimal places [duplicate]

Please look at this computations: a = N[Sqrt[2], 20]; N[a^2, 100] The output is 2.0000000000000000000, which is apparently not $a^2$ to 100 decimal places. ...
5
votes
0answers
82 views

Mathematica 9 Autocomplete Pop-up issue

I've just installed Mathematica 9.0.1 Student Edition on my Laptop and my Home PC. On my Laptop, it works just fine. But on my Home PC I get this weird issue of the pop-up command autocomplete window ...
-1
votes
1answer
129 views

Plotting the results of a system of equations

I believe this is a question of more list manipulation than plotting, but I hope you could help me. I solve numerically a system of equations of 3 variables, take only real solutions where one of the ...
2
votes
0answers
321 views

Remote kernel shuts down after several seconds

I have Mathematica 9 installed on two Windows Server 2008 R2 machines. Now i want to try using one of them as a frontend with local kernels and the other one for remote kernels. OpenSSH 6.5 for ...
3
votes
2answers
105 views

PlotRangePadding that's a fixed fraction of a plot's longest dimension

I am trying to produce plots of a region which can alternately become very long or very tall, and I would like to have some padding around it which is uniformly thick in both the horizontal and ...
7
votes
2answers
600 views

Morphing a “sheet of paper” into a torus

How can I visualise the standard topological "rubber-sheet" construction of a torus, that is, morphing a square into a torus? How can I start or are there any examples in the Mathematica ...
5
votes
2answers
177 views

How to customize derivative behavior via upvalues?

I'm having trouble getting customized derivatives (defined using upvalues) to behave in sane ways. By this I mean that I'd like to define a derivative using an upvalue and then have Mathematica apply ...
2
votes
3answers
159 views

Join matrix based on conditions

Given the following matrix: ...
1
vote
1answer
286 views

Error bar plot - no bars but rather point size determined by errors

Looking for a way to create an ErrorListPlot (x,y,error) with the radius of the PlotMarker ...

15 30 50 per page