3
votes
2answers
67 views

Simplifying a time-series segmentation Query

This query segments a time-series and filters out dropout frames. Can it be simplified - ie, made more readable? ...
2
votes
1answer
150 views

How can I plot a circular region and lines?

I am having difficulty plotting something along these lines in Mathematica. I will explain what is going on here. Basically, I am solving an interval equation $ax=b$, in the first example $a = [1, ...
1
vote
1answer
84 views

Need help solving a system of two 1st order nonlinear differential equations

The original system of equations reads: $\begin{cases} f'(r) + f(r) \left(a(r) - \frac{1}{r}\right) = 0,\\ f^2(r) + a'(r) + \frac{a(r)}{r} - 1 = 0\,, \end{cases}$ with boundary conditions $f(0) = ...
9
votes
2answers
94 views

Does Dataset round? [duplicate]

I'm importing the following Excel file: My code and its results are: ...
6
votes
3answers
71 views

Numerically integrating a list-valued function [duplicate]

I want to NIntegrate a List valued function foo[x] which is only defined for numerical ...
1
vote
2answers
65 views

How to define logical expressions for platonic solids?

A more general question would be: How to find logical expressions for 3D-objects described by closed polygon sets? Finally a simple question is more prolific, therefore: How to define logical ...
2
votes
1answer
30 views

Hypergeometric function with large parameters [duplicate]

I need an efficient and accurate method to evaluate hypergeometric ratios of the form: $$\frac{_{2}F_{1}(a+1,b;c;x)}{_{2}F_{1}(a,b;c;x)}$$ for large positive values of ...
0
votes
1answer
33 views

How to import a text file into Classify? [on hold]

I have a text file like as follows. { "XXX" -> "A", "YYY" -> "A", "ZZZ" -> "B" } I'd like to import this so I can send it directly to ...
0
votes
0answers
42 views

Getting long complex-valued integrals when simpler real-valued expressions exist

I have a long list of real-valued functions I'd like to integrate symbolically. For many of them, Mathematica gives me results with long complex-valued expressions involving weird functions such as ...
4
votes
2answers
75 views

Can't solve equation having complex coefficients

Why can't Mathematica solve $\quad\quad\frac{1-i}{\sqrt{2}}=e^{i \alpha } \tan \left(\frac{\beta }{2}\right)$ with the restrictions $\alpha \in [0, 2 \, \pi)$ and $\beta \in [0,\pi]$: ...
13
votes
4answers
603 views

“Indexing” a vector

I need to "index" a vector according to the first occurence of its distinct elements. I have written ...
0
votes
1answer
36 views

Using variables in file names during import/export [duplicate]

I have 23 .csv files named as 0.csv, 1.csv.... I'd like to import those files one by one, perform some manipulation on the data and finally export it as "i+20".csv. "i" is the variable which in my ...
5
votes
0answers
80 views
+100

Slow work of SQLInsert with SQLite

I want to store my data in SQLite database, but writing large numbers of data its too slow. For example: ...
0
votes
0answers
37 views

DSolve solves PDE only without boundary condition, but fails otherwise

I'm trying to solve for Te[w, Pprobe, t] in a partial differential equation. What's surprising is that it manages to solve it when I don't put in any initial ...
11
votes
1answer
111 views

Incompatible InterpolatingFunction between V9 (and earlier) and V10

I am encountering compatibility issues when loading DumpSave(d) definitions in V10 that have been created with earlier versions. V10 appears to be unable to digest ...
-1
votes
1answer
70 views

Formatting and inserting a parameter table into a plot

I'm fitting data, and I want to put the parameter table generated by NoninearModelFit into the plot. How can I do that in a reasonable way? I want to format the ...
5
votes
1answer
127 views

Simulation Sample Paths for Stochastic Approximation Algorithm

Let $X_t$ be IID random variables in $[0,1]$ and CDF $F(\cdot)$. Suppose there exists a variable $Y_t$ given by: $Y_1 = X_1$ and $Y_t = \phi(X_t, \overline{Y}_{t-1}), \forall t >1$, where ...
0
votes
1answer
46 views

How to find the value of a solution of an ODE at a particular point [on hold]

I'm trying to find the value of $z(y)$ at a particular time, say $y=0.5$. I've solved the differential equation. I tried using z3 = z[3] /. sol, but it's not ...
5
votes
1answer
78 views

Simple string pattern crashes kernel

The following code crashes my Mathematica kernel (v9, MacOS): ...
3
votes
0answers
55 views

Is it possible to recover the style of the previous version(V8,V9) in Windows?

In Wolfram Mathematica 10 (Windows paltform),the menu bar and files are combined together.When I narrow the window,it will become ugly shown as below! So my question is: Is it possible ...
0
votes
1answer
92 views
8
votes
1answer
247 views

How to execute JavaScipt on a webpage and then import the result on OSX?

I would like to import data from this page through Mathematica, http://www.oddsportal.com/soccer/netherlands/eredivisie/ . I tried importing through the default Import function ...
0
votes
0answers
28 views

Mathematica kernel does not work [on hold]

I define a function in Mathematica. Sometimes it may stop work without warning. Meanwhile, the color of the variable has changed a little. I have checked it. It comes from the integrate function.
0
votes
0answers
13 views

Trouble picking up package definitions [duplicate]

I open a new notebook and type ClearAll[test]; test[x_] := x + 42; I save it as Temp.nb and also as ...
0
votes
1answer
68 views

How can I write a function whose argument is a date, and whose output is the average temperature for the day? [on hold]

Consider I have some date, and I determine the average temperature for each day of the year. Using this, how can I write a function whose argument is a date, and whose output is the average ...
0
votes
0answers
40 views

NIntegrate with and without MaxRecursion

Ran a mathematica code using NIntegrate containing an integration over spherical and normal bessel functions. 1.Would the answer in the two cases change if I use MaxRecursion with some number of ...
2
votes
2answers
88 views

Making a conjecture concerning a certain upper-triangular matrix

I have searched for commands which will let me to create matrices and do matrix operations, but I don't know how to apply Mathematica to the following exercise. Make a conjecture for the result of ...
2
votes
1answer
102 views

RegionPlot3D run forever when plotting 3D ParametricRegion

when working with 2D, RegionPlot works fine with ParametricRegion as can be seen in this example: ...
2
votes
2answers
102 views

How to initialize several elements per iteration with Table?

I would like to initialize this kind of vector : {0,0,1,1,0,1,0,1,1,1,1,1} with Table. I tried ...
0
votes
0answers
49 views

Mathematica cannot find the c compiler

I installed Microsoft Windows SDK for Windows 7 and .NET Framework 3.5 SP1 Then, I installed Mathematica 10 trial version. I did: ...
20
votes
5answers
1k views

2D random walk within a bounded area

I want to simulate a random walk on two dimension in a bounded area such as a square or circle. I am thinking of using If statement to define a boundary. Is there a ...
1
vote
3answers
64 views

Store matched variables

Edit: I am matching and replacing a particular expression. At the same time... I want to store matched variables for later use. I got it to work with messed up code involving ...
3
votes
5answers
229 views

How to add periodicity to condition?

Is it possible to set the following function f[a], where a can be any real number? $$ f(\alpha) = \begin{cases} 1 ...
0
votes
0answers
83 views

Spectral Clustering

I am interested in the following question: How is it possible to check whether an algorithm is working properly? However, this question is too general for the post and I'd like to restrict attention ...
6
votes
1answer
81 views

Functional-Style Partial Application and the Accumulator Pattern?

Following up on Functional-style Fixed-Length Queue Object?, I want to generalize it to a functional-style accumulator pattern. Lots of things look like accumulators, loosely defined as binary ...
2
votes
2answers
95 views

Text to speech in notebooks?

Mac OS, MMA 10 -- I accidentally discovered that typing CtrlV between cells reads out the cell below, or, if you have text selected, reads out the text. CtrlV would be Edit > Paste on Windows, so ...
3
votes
3answers
71 views

Unexpected Behaviour with local variables and ToExpression

I encountered an unexpected behaviour in my mathematica-code, and want to understand whether that's a mathematica bug, or a misinterpretation on my side. ...
2
votes
0answers
44 views

Functional-Style Fixed-Length Queue Object?

Following up on question Side-effecting an array in an association? and @Mr.Wizard's answer in there, I'm modernizing and tweaking Daniel Lichtblau's efficient queues and ran into a little roadblock. ...
2
votes
1answer
110 views

Is it necessary to introduce ImplicitRegion and ParametricRegion in version 10?

In version 10.0, Mathematica introduced a new function about region plotting: ImplicitRegion. But I'm wondered that haven't this function been already existed in the older version? That is, ...
0
votes
2answers
59 views

Plotting3D Cylinders and planes [on hold]

How can I plot3D cylinders $y=1-x^2, y=1+x^2$ and planes $2x+2y-z=10, x+y+z=2$ in a coordinates system?(with Mathematica)
2
votes
5answers
131 views

Creating a conditional table

I'm trying to create a conditional table. Let's say I want to have such result: {1,2,3,4,5,0,0,0,0,0}. The idea is to create a table of n elements (10 in a given example), but when one element takes ...
0
votes
0answers
31 views

How to modify MagnificationPopUp menu values in notebooks [duplicate]

The default options in a MagnificationPopUp menu (50, 75, 50, 100, 125, 200, 300) are sometimes not sufficient to meet all user's needs. This may have more applicability when creating user ...
2
votes
2answers
138 views

Build tabular like Wolfram Tutorial Collections

In Wolfram Tutorial Collections,I see many tabular shown as below: My Trial Firstly,I copy the tabular template from the WRI ...
3
votes
1answer
77 views

Avoid writing explicit form of operator

I would like to evaluate the following (simplified) expression with Mathematica : $\frac{\delta}{\delta J} \exp[(J(x)+K(x)) \Delta (J(x)+K(x))]$ where $\Delta$ is a differential operator independent ...
2
votes
0answers
73 views

A problem about generating `[]` automatically

I have using the Wolfram Mathematica for two years.And I know the Mathematica has the operation Alt + ] that can generate []. ...
-2
votes
0answers
48 views

How do I find the coordinates of pont and plot the coordinates? [on hold]

I have a video file of a signature.How can i find the coordinate of points in the frames of the video?Also I want to plot x values as a function of time.How can i do such a thing?
3
votes
2answers
76 views

Side-effecting an array in an association?

I'm working on some classical data structures (stack, queue, etc.) and want to mimic oo style in MMA. As a first attempt, I want to store an array in an Association, like this: ...
1
vote
0answers
84 views

What's new in Mathematica 10 that begginers must know? [on hold]

Is there any new and Important feature in version 10 that the regular not-so-advanced Mathematica user must know? How do the new features of version 10 make the programing more efficient or faster? ...
0
votes
0answers
34 views

Crash on startup [on hold]

I recently changed my computer and have trouble with Mathematica on the new system. The installation completes without errors but immediately after clicking the Mathematica icon I get the message ...
10
votes
2answers
179 views

How can I decide whether a closed surface is intersected by a triangle?

A closed surface consisted of Polygons or GraphicsComplex and a triangle made by 3 points are in a 3D space. How can I decide ...

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