0
votes
1answer
4 views

option for Simplify command in mathematica

what does mean Simplify[%[[1]], %[[2]]] in following code? I mean [[1]] and [[2]] exactly what does refer to? ...
0
votes
0answers
8 views

Factoring an arbitary variable in mathematica

Imagine we have a equation like this ...
0
votes
0answers
14 views

Generating random numbers using Gaussian distribution in a code and changing standard deviataion in increaments

I am working on the following code, which calculates mean2 after taking mean/average over 100 realization of the code with each time 10 random numbers generated using Gaussian distribution. Currently ...
1
vote
1answer
19 views

Is this the right way to use for loop

Is this the right way to use for loop in order to find the sequence of $x_n$ ...
0
votes
0answers
23 views

unordered lists with maximum dispersion

As you can implement the following I have a list $$L = {p1, p2, p3, p4, p5 ........ pn}, n <50$$ I need cluttering and print this list 4 ...
0
votes
1answer
23 views

Boundary conditions for NDSolve

I get the following message: Boundary values may only be specified for one independent variable. Initial values may only be specified at one value of the other independent variable. >> from ...
0
votes
0answers
19 views

Getting DSolve to return different solutions

I am Using 10.0 I am trying to solve the following ODE: $$ \frac{d^2 \psi}{d\theta^2}+ \nu \psi =0$$ , $$\psi(0)=0$$,$$\psi(3\pi/4)=0$$ and Mathematica only sppits out the trivial solution PS: I am ...
0
votes
0answers
19 views

How to remove a hold from a result obtained by equating a partial derivative to 0?

I have a function g(x,y). I want to set its partial derivative by $y$ equal to 0, obtain an expression depending on $x$ and use it in further calculations. However, the code I am using puts a hold on ...
0
votes
0answers
37 views

Product of Two Functions

I wrote a little messy conditional probability distribution. In the output, however, the numerator shows like p^2 (A) (B|A), rather than ...
5
votes
3answers
95 views

Deriving a PDF for an annulus distribution

I would like to derive the PDF for an ''annulus'' type distribution, defined by the parameters $\theta\sim U(0,2 \pi)$ and $d\sim N(0,\sigma)$; where $\theta$ is the angle round a circle of radius ...
0
votes
0answers
21 views

Compute the Breslow-Day statistic in Mathematica

How would one compute the Breslow-Day statistic in Mathematica? Is it part of an existing package or can it be derived from one?
4
votes
0answers
27 views

Trouble exporting graphics to SVG (or PNG)

I'm trying to export a Graphics object to SVG (or, failing that, PNG). The graphic is a chart of ~1000 simple geometric "configurations"; below is a small excerpt ...
5
votes
1answer
33 views

KaryTree of Text .csv and Correlation

How can I make a KaryTree of this raw-data (raw-data at the end of the question): This is is data from a political survey in which I ask 5 questions with the following possible answers: Q1: 'Y'= ...
2
votes
0answers
54 views

Mathematica gravatar engine?

This question asks about making gravatars in Mathematica, but the accepted answer is just a wrapper around the gravatar.com service. Is there an open source Mathematica engine that performs the ...
1
vote
1answer
30 views

Cartesian coordinates inside Spherical function

I would like to write a function that draws a graphic object and its projections along the x,y and z axes. I specify the $r,\theta, \phi$ of the object and an arrow and it's dashed projections are ...
0
votes
0answers
13 views

How to handle DLL dependencies between .NET dll and non-.NET dll's

I think my problem arises because I am successful with loading a .NET assembly, creating an instance and calling methods from a .NET dll. Certain methods, however, call methods from other non.NET ...
0
votes
0answers
30 views

Integrate fortran function into Mathematica

I was trying to use Fortran function in Mathematica. I was following mainly this answer . My Fortran code looks like this: ...
-1
votes
1answer
22 views

CompiledFunction::cfsa Argument x at position1 should be a machine-size real number

I have a compiled function: g:=Compile[{{x, _Real}},...] and call g through an interim function: g2[x_?NumericQ] = g[x] If I call g2[100.], I get the CompiledFunction::cfsa : argument x at ...
0
votes
1answer
19 views

Series Soln False error

When I try to define my equation : sys3 = {y'[x] == 2 y[x]/(1 + y[x]^2) - Exp[y[x]]/(1 + Exp[y[x]]), y (0) == 1} OR ...
1
vote
1answer
25 views

How to return multiple types in APIFunction?

I'd like to publish an api that returns an image as well as a number, but it seems that the docs for APIFunction specifies only a single possible format type: Here's an example to play with: ...
0
votes
1answer
28 views

rescaling X axis

I have a pretty simple code, working fine and producing a plot that is ALMOST what I desire: ...
1
vote
1answer
27 views

A question on JordanDecomposition in Mathematica

How can I have Mathematica show me also the inverse matrix of the similarity matrix of JordanDecomposition of a matrix? Obviously I need to use here the ...
0
votes
1answer
24 views

List of Inequalities in RegionPlot with different colors

Starting from the example of the Documentation: RegionPlot[{x^2 < y^3 + 1, y^2 < x^3 + 1}, {x, -2, 5}, {y, -2, 5}] Which gives a nice plot with two ...
0
votes
0answers
29 views

differentiating an integral

I am new to Mathematica. i hope to have the software next week so please excuse the unusual syntax. p(y) means p is a function of y. u(p) means u is a function of p . p(x) is the value of p when y=x ...
1
vote
2answers
55 views

How to obtain the data of the intersection line of two surfaces?

I can plot the intersection line of two surfaces $f$, $g$ by using: ...
0
votes
0answers
23 views

Plot3D gives an empty box [on hold]

I have two questions. I am trying to 3d plot a function like in the image below. It gives an empty box displaying no results. I tried adjusting the graphic qualities, but it does no solve the ...
1
vote
2answers
62 views

Double sum in mathematica

It may look like a stupid question, but I was really confused by how double sums works in mathematica: After simplification, the function actually has nothing to do with n2? Also, when I manually ...
0
votes
0answers
15 views

Measuring space complexity?

I like using GeneralUtilities function BenchmarkPlot for estimating time complexities, is there something similar for ...
0
votes
1answer
36 views

Plot for function that calculated direct with while, but is piecewise

For this question Use of {FOR, Do, If,Plot} that ..., I wrote this code: ...
5
votes
1answer
35 views

Run several input cells in parallel

I have a notebook with several input cells that produce data which is then plotted into separate graphs. Since I do not want to save the results, because it makes the file huge, I keep the ...
1
vote
2answers
67 views

Definite integration in mathematica

I tried to integrate the following in Mathematica. $\int\limits_{-\infty}^\infty\cfrac{\text{e}^{\text{i}ax}}{x^2-b^2}\text{d}x$ where $a,b>0$ The analytical result is well known. ...
3
votes
1answer
82 views

To style Sound object

While doing some signal processing research my aesthetic feelings were heavily struck by following output: The problem here is that 211.96 s label is partially ...
1
vote
1answer
70 views
3
votes
1answer
43 views

Multiple pattern test in the definition of a function

I have a very simple question, and I'm sure there is a way to do this but I cannot find it: if I want to create a function that's defined only for matrices, I can do it like this: ...
1
vote
2answers
72 views

Plotting logistic maps

I have a question about plotting in Mathematica in general, and this particular recurrence relation as an example: $\qquad x _{n+1} = rx_{n}(1-x_{n})$ How can I plot the following plots as shown ...
0
votes
0answers
20 views

Make an existing solution for monitoring parallel jobs robust against dying kernels

Is there any chance to make the solution by @David here http://mathematica.stackexchange.com/a/1562/21606 more robust in the following sense: In my case, some parallel kernels die regularly during ...
0
votes
1answer
31 views

An unexpected NDSolve behavior [on hold]

I observe the following. The code: ...
0
votes
0answers
25 views

Setting Initial Conditions in a System of Differential Equations that don't start at t=0

I have a system of six differential equations (linear for the sake of the discussion). I want to set the initial condition to start at time t=18 and not time t=0. I know the values of the dependent ...
1
vote
1answer
27 views

Importing an .eps file failed in the latest version of mathematica

It was quite straight forward to import an .eps file (also pdf and other formats) into a script, with the version 10.0. that I had before; but, since I upgraded my Mathematica to the latest version ...
0
votes
4answers
46 views

Matching a Table and a List and building a new Table

I have a Table which includes {Numbers, Probabilities}. For example A= {{1,0.5},{2,0.25}, {3,0.1},{4,0.9}……{100,0.1}}. Put attention that the numbers are 1,2….100 in order. I have a List of random ...
4
votes
1answer
65 views

How can a function without an operator form be used in postfix form?

As an exercise, I was trying to convert the following Clojure code to Mathematica: ...
1
vote
1answer
51 views

Using Mathematica to batch-produce text files

I need to make a bunch of plaintext files, all of which differ only in a single parameter. The text I want to "copy" or "batch produce" is a little bit complex, since it contains quoted areas and ...
0
votes
0answers
23 views

Solving Time-Dependent PDE's Analytically with no non-trivial Boundary Conditions

I'm having some trouble solving a partial differential equation that is supposed to model the propagation of a scalar field in Schwarzschild spacetime using spherical coordinates. I'm using the DSolve ...
0
votes
0answers
29 views

A function for replacment in mathematica [on hold]

when you have too many replacements such as a1 x+ b2y + c1 z/.{a1->s^2+b^2,b1->r^2+g^2,c1->f^2+k^2} is it possible to define a vector like this ...
4
votes
1answer
58 views

How can I make an invisible Cell?

Notebooks have a Visible option, but Cell // Options doesn't mention any equivalent for ...
-2
votes
0answers
24 views

how to know two aircraft getting far away each other? [on hold]

Dataset: my algorithm is: calculate velocity vector each aircraft ...
4
votes
2answers
224 views

How do I encode this replacement rule?

I'm pulling a 5x5 array from a larger array. The small sub-array (call it S) can contain any combination of the symbols A, B or 0. What I'd like to do is: if the array contains any matching pairs ...
2
votes
0answers
42 views

Why can Mathematica compute numerical sums more efficiently when they are written as matrix operations?

Let $f(n)$ and $K(n,m)$ be functions such that the double sum, which we wish to evaluate numerically, $$ \sum_{n=1}^a \sum_{m=1}^a f(n) f(m) K(n,m) $$ exists when $a$ is some large positive number. I ...
5
votes
0answers
40 views

How to find the concave points of a point-set?

To solve the boundary of a set of planar geometry, I sampled $6$ graphs, then using RunnyKine's approach. ...

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