0
votes
1answer
142 views

Patterns of function-arguments in expressions

I want a function that compares an expression with a specific pattern. The expression has always the following form: ...
1
vote
1answer
146 views

Unexpected output from oddSublists [duplicate]

I have just bought Mathematica and I'm in the process of plowing through Shifrin's great book. On page 74 the function oddSublists doesn't give me the expected ...
0
votes
1answer
110 views

CurveGraphics for 3D System of DEQs

I am using the CurveGraphics6 NB to try and do some 3D related phase portraits and graphics. The following works and produces an animation. ...
0
votes
0answers
168 views

Savitzky-golay filter

How to use Savitzky-golay filter on csv file? I have file.csv in this format: 0.1,1.6,2.8,0 0.2,1.2,2.3,1 0.7,1.5,2.4,2 0.6,1.2,2.7,3 0.4,1.4,2.9,4 0.3,1.3,2.5,5 ...
2
votes
1answer
224 views

Nested Derivative

These two expressions are mathematically the same, but when substituting with the same rule, yield different results. What is happening? ...
1
vote
0answers
23 views

$H_{\infty}$ optimization of transfer function matrix [duplicate]

I have a two-dimensional $(2 \times 2)$ transfer function matrix like this: $$G(s) = \begin{pmatrix} \frac{1}{xs+1} & \frac{1}{s+0.5}\\ \frac{3}{s+3}& \frac{1}{ys+2} \end{pmatrix} $$ The ...
1
vote
1answer
120 views

Collecting terms in an expression [duplicate]

I have an expression: ...
1
vote
2answers
195 views

Cropping a Plot without rasterization

Suppose that I make a plot of $x^2$ vs. $x$: myPlot = Plot[x^2, {x, -1, 1}, Frame -> True] If I click on the plot, I see the orange handles with which I can ...
2
votes
1answer
129 views

SSH known hosts in Windows (Error code = 124)

I had to re-install Raspbian OS and now it has new SSH key. SSH clients usually let ignore this fact and save the new key, but not now. Mathematica gives no way to go if the Host Key was changed. I ...
10
votes
1answer
188 views

Sporadic bugs in multidimensional SparseArray objects

Udate This SparseArray[] bug is (apparently) fixed on version 10.0 ...
13
votes
2answers
444 views

Most influential and/or disrupting features introduced with new versions of Mathematica

This is something that has been bugging me for ages. With every upgrade, Mathematica has added new functionalities and amendend some of its bugs. In the process, though, some older functionality has ...
2
votes
1answer
171 views

Saving a graph of a great number of nodes

I'm developing a code where I get graphs with over 10K nodes. These graphs have a particular relationship between clustering and degree that I need to save for future analysis. The problem is when I ...
1
vote
1answer
773 views

Euler's method for system of differential equation

I need to program Euler's method to solve a system of two diffferential equations of first order. Fist, I have programmed the Euler's method for just one differential equation: ...
9
votes
1answer
406 views

Where to download the MathWorld package?

I was trying to run some notebook I downloaded from MathWorld, but lots of them need << MathWorld`Curves` I tried to google it , only to find this, but ...
8
votes
2answers
209 views

The introduction for Context in Wagner's book is out of date? [duplicate]

In Section 8.1.1 (P230 of the book, P249 of the PDF) of Wagner's book, the following example is shown: x = 5; temp`x = 6; Begin["temp`"]; {x, Global`x} The ...
1
vote
1answer
164 views

Fitting data using a series of Sin and Cos

I have the following data representing the normal displacement caused by a normal load applied at the middle cross section of a cylinder: I've made the data available here. I am trying to fit ...
3
votes
2answers
147 views

How do I NOT change the input/output number when editing?

I tried to search for a topic on this, but didn't seem to find anything, so here goes. I'm pretty new to Mathematica, so there are a lot of things I don't know yet, but one thing is pretty annoying ...
5
votes
2answers
155 views

Improving performance in the generation of random (directed acyclic) graphs

I need to generate large (directed, acyclic, transitive) graphs. My code in Mathematica gets very slow for large numbers of vertices. I've tried a number of approaches and I can't find any significant ...
2
votes
1answer
156 views

The output is the same as Input when I add the boundary conditions to a PDE

I am trying to solve a PDE in the first order with specific boundary conditions. When I solve use DSolve without the boundary conditions, Mathematica gives me an answer in an arbitrary function. When ...
0
votes
3answers
150 views

How to combine multiple functions into a single function, indexed bya new argument

I have a system of expressions (matrices) which correspond to increasing orders of precision in a theory. These expressions are quite complex (require about 40+ lines of code to produce) and are not ...
1
vote
2answers
202 views

Summing Over a Variable Number of Indices

I am trying to figure out the best way to include a variable number of indexes of summation in a program. For example: Suppose I want to define a function $g[n,s]$ that returns the sum ...
3
votes
1answer
140 views

Arguments for ChartElementFunction

I was reading the documentation for BubbleChart and I saw this example ...
1
vote
1answer
139 views

Simulation code performance tuning

The following simulation takes over 20 seconds for evaluation. I have difficulty re-coding it with Nest and Map or Compile functions to make it more efficient. Can some one help with this? The ...
1
vote
1answer
173 views

combining manipulate with “static” plot

Is there a way to show a plot of a "static" function as background for a manipulate panel ? In other words: I have put into a manipulate a trajectory (solution of a system of two differential ...
1
vote
0answers
296 views

Slow mixture fitting when having ill-conditioned covariance matrices. How to make it faster?

I'm using Mathematica 9.0 to fit multidimensional observations with a gaussian mixture. To do so I first adapted these steps to ensure that the mixture parameters are well defined (see ...
1
vote
1answer
296 views

Can ParametricNDsolve be used for coupled PDEs with 5 parameters?

I have a system of coupled PDEs with five parameters that I only know ranges for rather than explicit values, and I was wondering if I could define a parametric equation with ParametricNDSolve and ...
2
votes
1answer
195 views

Render dynamic Graphics objects static

As was discussed in the comments of another question (MathLink Graphical Output (Plots) to File), Graphcis objects produced by commands such as ...
0
votes
1answer
168 views

How to format the data in a table to have only numbers

This question is in continuation of my earlier query, how to store output of a function in a table for future use. I am able to store the output of my function in a table, however the table consists ...
9
votes
3answers
1k views

Why does Simplify[b-a] give -a+b and not b-a?

Simplify[b - a] results in -a + b. I prefer b - a, which is a bit simpler (3 symbols instead ...
2
votes
1answer
138 views

Determine types of input, output and internal variables in compiled functions

I am trying to speedup the computation of a longer function using Compile. For illustration consider the following short example: ...
3
votes
1answer
957 views

How to obtain the orthogonal matrix that diagonalize a symmetric matrix [closed]

I have a real symmetric matrix H which is in symbolic form, I need a matrix P that can diagonalize H; also P is orthogonal and its columns are the eigenvectors of H. How can I doing this in ...
2
votes
1answer
137 views

Using IntegerPartitions for distinct integers

What I would like to do is to find a way to test how many ways m distinct integers from the set {1,..., n} where ...
1
vote
2answers
223 views

2D Fourier transform of a table - ArrayPlot issue

Recently, I have encountered an issue with ArrayPlot after performing a Fourier transform of a table. Picture presented above is an ArrayPlot of a 2D table. Using Fourier on this 2D table I obtain ...
3
votes
2answers
259 views

Resizing graphics with an inset when exporting

I am generating a number of graphics using Mathematica that contain text. Adding the text to the graphic has been a considerable challenge, but I have finally come up with the following: ...
0
votes
0answers
47 views

How to add a subplot in corner of plot? [duplicate]

How is something like the plot with subplot shown in this image achieved with Mathematica?
2
votes
0answers
36 views

Adding Elements to a List of Lists [duplicate]

I'm trying to do the following: Given a function f[x,y], I want to turn the list {{x1,y1},{x2,y2},...,{xn,yn}} into ...
0
votes
0answers
69 views

Converting a BSplinecurve to function

I am having two set of data. This is d000 and d001. The set d001 is a subset of d000. I am fitting the d000 data by using the BSpline of the d001 data according to the following commands: ...
1
vote
1answer
128 views

Read expression from Mathematica via Mathlink C++

This is a simple C++ program to send an expression to the_Mathematica_ Kernel and get its response. ...
5
votes
2answers
495 views

Multiply each element of an array by another array?

I would like to multiply an array by each element of another array, and am having a lot of trouble finding a built-in or automated method of doing. Here is an example of what I'd like to achieve: ...
9
votes
8answers
375 views

Fast way to get positions of “boxed” array elements?

Given a 2D array (arbitrary numeric / evaluates to numeric elements, simplified for examples, and can be arbitrary dimensions so long as the operation makes sense, I'm working with 2K X 2K in my ...
1
vote
2answers
321 views

If/else re-evaluate (integer only solutions)

I am trying to get Mathematica to do an if/else loop. I can get as far as the if, but I would like it to re-evaluate until only integer solutions are found. Here is what I have: ...
1
vote
2answers
190 views

Using Array Elements as Function Arguments

Suppose I have an array p = {a,b,c,d} and a function f that takes a variable number of arguments. I want to evaluate ...
3
votes
2answers
202 views

Defining an anonymous function using another function but with fewer arguments

In MATLAB you can use an anonymous function with another function to define a new function with fewer arguments as long you define the excluded argument before, e.g. ...
0
votes
1answer
816 views

Evaluate function of two variables using nested Do loops

Is there a more efficient way of evaluating a function of two variables on a rectangular grid the the following nested Do loops? ...
7
votes
2answers
253 views

Is there a function which instantly tells you whether an element is part of a list?

I have a very long list of numbers and I want to check whether there's a function (something that would look like PartOfQ[element,list]) that tells you immediately ...
3
votes
1answer
70 views

Markup of CDF file, e.g. highlighting text

Is it possible to markup (i.e. highlight or underline) text in a deployed cdf file and then save it? I think I know the answer (no), but since it seems a basic necessity for a document format that ...
3
votes
0answers
119 views

Using Graph to cull correlated lists

I have a set of lists that represent molecular descriptors. I need to identify which descriptors are highly correlated and eliminate the correlated pairs. I can represent the connectivity by ...
0
votes
1answer
212 views

How to apply a conformal map to a jpg (or other image)

I would like to apply a conformal map to a jpg. For example, the map $z\mapsto z^2$ to this image: http://thumbs3.ebaystatic.com/d/l225/m/mGyeriV7l-YArkeBd9oMUng.jpg Any help on how to do this?
2
votes
2answers
181 views

Solving a dynamic program via recursion

I'm trying to use recursion to solve a joint inventory/ dynamic pricing problem as in monahan, petruzzi and zhao 2004. I tried to solve for y[t] and ...
1
vote
1answer
64 views

MLEvaluate() Function Gives Error

I am trying to link my C++ program to Mathematica Kernel. I am trying to use the MLEvaluate() evaluate but I receive an error while compilation. My codes are as below: ...

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