# All Questions

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? ...
8 views

### Factoring an arbitary variable in mathematica

Imagine we have a equation like this ...
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 ...
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 $x_n$ ...
20 views

### How do I extract the values returned as Root[,] after solving the Sturm Liouville problem to take the square root?

$y''+\lambda y=0, y'(0)=0,y(1)+y'(1)=0$ ...
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 ...
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 ...
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 ...
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 ...
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 ...
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 ...
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?
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 ...
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'= ...
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 ...
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 ...
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 ...
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: ...
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 ...
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 ...
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: ...
28 views

### rescaling X axis

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

### Measuring space complexity?

I like using GeneralUtilities function BenchmarkPlot for estimating time complexities, is there something similar for ...
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: ...
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 ...
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. ...
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 ...
70 views

### Use of {FOR, Do, If,Plot} that are in one code?

I wrote this code: ...
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: ...
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 ...
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 ...
31 views

### An unexpected NDSolve behavior [on hold]

I observe the following. The code: ...
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 ...
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 ...
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 ...
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: ...
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 ...
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 ...
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 ...
58 views

### How can I make an invisible Cell?

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

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

Dataset: my algorithm is: calculate velocity vector each aircraft ...
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 ...
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 ...
To solve the boundary of a set of planar geometry, I sampled $6$ graphs, then using RunnyKine's approach. ...