1
vote
0answers
73 views

Trying to plot two coupled equations modeled through Ito Process

I have a system of two coupled equations which I have first examined without noise and have obtained a streamplot for it, to look at the trajectories. Code for this is here: ...
1
vote
1answer
41 views

How do I match all the subscripted terms in Times?

Suppose I have an expression: $W = A_{i,p,q...}\,\, a_ia_ja_ka_l...$, where $A_{i,p,q...}$ is an expression that does not depend on $a$, the indexes $i,j,k,l,p,q...$ are integers and all the integers ...
0
votes
1answer
72 views

Using custom ticks with RegionPlot3D

I'm trying to change to plot a sphere using RegionPlot3D and look at how the shape of the sphere changes when you use a logarithmic scale (or any nonlinear scale) ...
0
votes
1answer
138 views

Import GEXF graphs into Mathematica?

Is there any smart way to import gephi graphs (*.gexf) into mathematica ? I mean other than converting to *.gml.
0
votes
1answer
188 views

ListDensityPlot and RegionFunction

I have the following ListDensityPlot : ...
4
votes
1answer
264 views

Aligning Overlay and GraphicsGrid plots

I need to make several plots displaying a ListPlot overlaid with a Histogram and close to it (ideally even sharing X axis) a ...
5
votes
3answers
1k views

Complex conjugate

How do I complex conjugate a vector? ...
25
votes
7answers
759 views

Faster position list construction from a “take instructions” list

Take some list, e.g., {1,2,3,4,5}, and a "take instructions" list, say {1,1,2,1,1}. The latter is read as "take the first ...
0
votes
1answer
233 views

Numerical integration and plotting

New to Mathematica, and trying to numerically evaluate two integrals: ...
1
vote
0answers
191 views

Collision detection algorithm (discrete) with sweep and prune algorithm for periodic boundary conditions

EDIT: Question Updated with solution approach, but solution much slower than original implementation. Any ideas to speed up implementation? In the discussion on collision detection (see here) I asked ...
5
votes
2answers
214 views

Problem using Rotation in Show

I would like to have an animation of rotating box and displayed it with other elements (not rotated) using Show. The first step to do that is to have all the elements working properly. So I did the ...
2
votes
1answer
91 views

How to make Simplify/Expand work in patterns?

I am trying to calculate deriv of a complicated function and store the values for reuse. But the FullSimplify in my definition doesn't seem work all the time: ...
5
votes
2answers
260 views

Time Zone Conversion

I use Mathematica to administer my share depots. The depots contain shares of many different time zones. I update the depot values several times a day. My problem is that Sidney, Australia, (it might ...
7
votes
2answers
186 views

How to draw a family of planes and its envelope?

Motivated by a question in MSE, I have the following question: How can I visualize the envelope of the family of planes $$ 2ax+2by-z+a^2+b^2=0, a,b\in\Bbb{R} $$ which is given by the ...
-1
votes
1answer
168 views

Reading Barcode/QR Code from webcam

I need to make a Barcode/QR code reader from video. It could be captured from an image with a built in code, but I could not figure it out how it could be done by video. Let me tell the big picture. ...
0
votes
1answer
105 views

axis label text rotation

I've got the following script: ...
1
vote
1answer
311 views
0
votes
1answer
763 views

What if do NOT want Mathematica to normalize eigenvectors with Eigenvectors[N[matrix]]?

ORIGINAL QUESTION Question speaks for itself. Mathematica normalizes the eigenvectors automatically when you type Eigenvectors[N[matrix]]. What if I do NOT want ...
0
votes
1answer
59 views

Simplify huge output or using the output without showing it in full [closed]

I'm trying to solve a system of differential equations. It works fine but Mathematica creates a huge output, which, when shown in full, results in a file size about 100 mb. Using Simplify doesn't work ...
19
votes
1answer
629 views

Capturing Data from an Android Phone

Is there a way to capture Data from an android phone to be later analyzed in Mathematica?
1
vote
1answer
67 views

How to prevent automatic simplification in InputField?

Here is a basic example: {InputField[Dynamic[x]], Dynamic[x]} This code generates an input box with and dynamic display. What is disturbing me is that when ...
1
vote
0answers
226 views

Cell counting from an image file [closed]

I have a lot of cell culturing pictures. One of the example is as follows: Every black dot represents a cell, and I need to count only the cells on the image. I have a code to detect and count the ...
2
votes
1answer
210 views

Efficient tensor product followed by contraction [duplicate]

Say I want to efficiently evaluate $\sum_{kl}A_{ikjl}B_{kl}$ where $A$, $B$ are numerical tensors. This has been discussed before but with no focus on efficiency. A straightforward way as mentioned ...
5
votes
1answer
213 views

Slow exponential evaluation over lists

This question,which is still unanswered, might be relevant because it involves NIntegrate over lists and it also has Exp. In ...
7
votes
1answer
230 views

How to set the Y coordinates for a Graph with defined X coordinates to prevent overlap of nodes?

I would like to draw a Graph with defined $x$ coordinates and variable node sizes. If I simply replace the $x$ coordinates of a graph, then nodes can overlap and ...
0
votes
1answer
1k views

Including error bars on graph in Mathematica [duplicate]

Mathematica ListPlot function allows me to plot the above data with omega on the x-axis and CD on the y-axis 1) How do I incorporate the error bars in my data on the graph? 2) Are there any basis ...
0
votes
1answer
192 views

FindRoot over a function with some constant variables

I would like to perform the FindRoot command over the function func. Suppose: ...
5
votes
2answers
170 views

Button that starts an evaluation which is monitored with a progress indicator

I have a DynamicModule in which I which I wish to start an operation (actually import files) with a button. I would like to monitor the progress with a ...
0
votes
1answer
71 views

Making a simple text log file

I have a model and want to export the run parameters to a log file. The idea is to get the following example into a decent text export: ...
0
votes
0answers
27 views

Substitution employed to DSolve [duplicate]

How do we get Mathematica to express generally what substitution has been employed in obtaining DSolve outputs? e.g.for solving particular: $ \int \sqrt {\sin^{-1} {\sqrt x }}dx $ EDIT1: ...
2
votes
1answer
294 views

Positioning a subplot using Inset in the main plot with image or scaled coordinates

I have generated a plot and subplot fine, and I would like to position it in the top right corner of the main plot. Ordinarily I would use the position options. However, my notebook is used for ...
2
votes
1answer
114 views

Mathematica output format

Basically Mathematica is giving me outputs in a format I do not recognise. I've just started Year 12, so there are mathematical terms I do not understand. For example, ...
0
votes
0answers
88 views

Finding roots by solving its ODEs [duplicate]

Roots of fluctuating function (p,q real) needed to evaluate eigenvalues of $$ y(x) = \dfrac{\sin px }{p} + \dfrac {\sin q x }{q} =0 ...(1*) $$ form a real and complex infinite set. The way to ...
2
votes
1answer
487 views

Working with derivative of conjugate of a complex number

I have a complex function, lets say $g(x)$. I want to take its and its conjugate's derivative. I need the solution of derivative which must be symbolically and computationally efficient. Lets take an ...
1
vote
2answers
216 views
0
votes
2answers
102 views

Convert Range to List of Strings

I need to generate the result given by ...
0
votes
1answer
39 views

Defining a function then using it in DSolve

Probably a pretty simple question but I've been stumped for awhile looking around. I'm trying to solve four diff. eq.'s using DSolve and some of these equations depend on a function B[t] which I try ...
1
vote
1answer
152 views

Iteration convergence of Newton approximations

I am trying to determine for which initial values Newton's approximation of specific functions (EX: f(x)=x^2 -1)converge and to what numbers it will converge to. *Where Newton's approximations are x[...
2
votes
1answer
110 views

Getting the first $n$ terms of a recursion relation

Given a recursion relation, I would like to generate the first $n$ terms (automatically) without having to go term by term. Background Each term is of the form $a_{n}(t)$, that is, $a_{n}$ is a ...
7
votes
3answers
318 views

Find the eigenvalues for an ODE

For example, say I have $y'' + \lambda y = 0$ and the endpoint conditions are $y'(0) = 0$ and $y'(\pi) = 0$. How can I find the values for $\lambda$ that for which there is a non-trivial ($y\neq0$) ...
1
vote
0answers
53 views

Using Nearest on a 2D List (seeing extra parentheses)

I am working a problem involving colliding particles. I define a list of particle diameters (effectively a bin distribution). I need to know if two particles collide, in what bin diameter should I ...
6
votes
2answers
83 views

SetSystemOptions in a package

I'm looking to update a large package (with subpackage files called in the same context) to be compatible with version 10. A lot of the functionality surrounds plotting, particularly some custom ...
4
votes
0answers
90 views

Wrong Cashflow of Annuity with initial payment

If we use TimeValue to look at the PV of an Annuity with initial payment: The initial payment ...
1
vote
0answers
177 views

Adding a point label to a moving arrow vector [closed]

Consider: ...
0
votes
1answer
183 views

Simultaneously fitting two data sets to two functions is too slow [closed]

I have to fit two data sets to two functions(eps1,eps2) with same parameters (w0,f,g) Initially, I know only one function ...
1
vote
0answers
51 views

Simplifying And of equality expressions

This expression does not automatically simplify to False: a == 0 && a != 0 ...
0
votes
1answer
54 views

What's wrong with the code?

The following code doesn´t fill the base of the picture. ¿Why? ...
13
votes
2answers
554 views

What is the fastest way to get the nth distinct permutation of a list?

What is the fastest way to write a function nthPermutation[xs_List, n_Integer] which is equivalent to Permutations[xs][[n]] but ...
0
votes
1answer
149 views

Is there a better way to download images in parallel?

Is this the best way to batch save a list of image urls in parallel? ...
0
votes
1answer
135 views

Creating a random make matrix with a particular rank

Does Mathematica have a built-in function that will return a random mxn matrix with rank r?l

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