# All Questions

18 views

### Mathematica Workbench - when to expect an update?

I'm considering getting Mathematica Workbench 2. Looking at the videos on Workbench 2 and on "Profiling Mathematica code" @ 01:09 I see the current version nr 2 dates back to at least oktober 3 2007 ...
7 views

### Spherical harmonic derivative

Consider the following substitution Derivative[2, 0][S][th, ph] /. S -> Function[{th, ph}, SphericalHarmonicY[3, 0, th, ph]] which gives correct answer. While ...
28 views

### How to get a number from Solve

It's often useful to get just one number from Solve. I use the following construction for acquiring one solution from the expression returned by ...
8 views

### Parallel kernels won't start

On my new MacPro (on Mavericks) Parallel kernels will only start if the Master kernel is the standard one with name Local. My other added Master kernels will work but any Parallel Kernel evaluation ...
22 views

### executing a mathematica packet from within java

i have this package.m that i am trying to call to from within java code using netbeans, however it does not seem to be responding. how can i test to see that i am actually connecting to Mathematica? ...
52 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: ...
55 views

### Unexpected output from oddSublists

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 ...
51 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. ...
54 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 ...
21 views

### exporting to a wav file [on hold]

can someone help me with exporting this into a .wav file? my code in mathematica is: Play[Sum[Sin[(1 - 1/n^2)*2 [Pi]*t*440] + Sin[(1/4 - 1/(n + 1)^2)*2 [Pi]*t*440], {n, 2, 10}], {t, 0, 3}] ...
148 views

### Nested Derivative

These two expressions are mathematically the same, but when substituting with the same rule, yield different results. What is happening? ...
21 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 ...
48 views

### Collecting terms in an expression

I have an expression: ...
74 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 ...
33 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 ...
49 views

### Sporadic bugs (?) in multidimensional SparseArray objects

What appear to be sporadic bugs (?) in multidimensional SparseArray objects (?) are plaguing our code development efforts. ...
123 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 ...
96 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 ...
123 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: ...
72 views

I was trying to run some notebook I downloaded from MathWorld, but lots of them need << MathWorldCurves I tried to google it , only to find this, but ...
147 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; tempx = 6; Begin["temp"]; {x, Global`x} The ...
51 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 ...
49 views

### For loops overwriting dynamically named lists [on hold]

For some reason the following code is overwriting previous loops with the present one, and I really don't see why it is doing it. I included the output to show. Any clues? ...
63 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 ...
69 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 ...
48 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 ...
66 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 ...
40 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 ...
57 views

### Arguments for ChartElementFunction

I was reading the documentation for BubbleChart and I saw this example ...
28 views

### i do not understand why NSolve::ivar error is occouring? [duplicate]

PLEASE HELP v[t] = Sqrt[(x'[t])^2 + (y'[t])^2 + (z'[t])^2] NSolve[{z''[t] == -9.8 - 0.0154 z'[t]*v[t], y''[t] == -0.0154 y'[t] v[t] + 0.0033 x'[t] v[t], x''[t] == v[t] (-0.0154 x'[t] - 0.0033 ...
70 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 ...
78 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 ...
22 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 ...
45 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 ...
92 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 ...
75 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 ...
793 views

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

Simplify[b - a] results in -a + b. I prefer b - a, which is a bit simpler (3 symbols instead ...
29 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: ...
43 views

### Taking the conjugate of a user defined function

I have a function like this: \$\frac{e^{-\frac{r^2}{2}-i (\alpha +2 \phi )} \left(2 \left(r^2-1\right) e^{i (\alpha +2 \phi )} \sin (\beta )+e^{2 i \alpha } r^2 (\cos (\beta )+1)+r^2 \left(-e^{4 i ...
74 views

### How to obtain the orthogonal matrix that diagonalize a symmetric matrix [on hold]

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 ...
67 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 ...
31 views

### Simultaneously fitting data sets with many variables as free parameters

I found a partial answer in the documentation centre, but would like to expand on it and know how can I fit multiple sets of data and extract the parameters from them. It is an eigenvalue problem - We ...
74 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 ...
103 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: ...
73 views

### how to store output of a function in a table for future use [on hold]

I am new to Mathematica and if this is a simple query - please excuse me for the same. I am trying to solve a equation which is a function of two variables. From the solution, I need to store the ...
35 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?
32 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 ...
30 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: ...