# All Questions

118 views

### BarChart rasterized in EMF export

My boss wants several Mathematica graphics as vector graphics in EMF format. All my plots are exported neatly, except for a BarChart which gets rasterized for no apparent reason: ...
112 views

### Saving data from NonlinearModelFit

If you use NonlinearModelFit the results are put into some sort of output package. How do you save these packages so that you can go back to them later? My particular problem is that I generating ...
188 views

### ListPlot with conditions

I have a data file containing the position of about $10^5$ stars of a spiral galaxy. Here is the plot and this is the corresponding code ...
293 views

### Expectation of a family of random variables

I did some search here, but seems that no one asked about this. I want to define a family of independent and identically distributed random variables, $x_1,...,x_n$, and then calculates the expected ...
178 views

### Determining the dimension of a probability distribution

Functions like Mean and RandomVariate clearly infer the dimension of the distribution passed to them. One can also usually ...
257 views

### Fixed-Point Numbers in Mathematica

I am working with a library that needs input in a Fixed Point notation. I’d like to figure out a way to convert the floating point results into fixed point representation. The fixed point length is ...
517 views

### FindRoot giving false roots with Bessel Functions

I have read in some places about the errors associated with FindRoot, but the closest thing I can find on this website seems to be due to the imaginary unit. I am dealing with what should be a ...
289 views

### Selecting for 2D points that are within a threshold distance of an upper- and lower-bound number of points

I have a very large set of 2D points: numberOf2DPoints = 10^6; pointList = RandomReal[{0, 1000}, {numberOf2DPoints, 2}]; I'd like to find a way to quickly ...
276 views

### How to partition a list into sublists in a similar way to Histogram

I have a list of list as below (I show part of it) ...
235 views

### Separating disconnected graph objects without losing vertex coordinate assignments

Say I have a graph Gtest, which has multiple disconnected components. I found that I can isolate individual components while retaining vertex coordinate ...
393 views

### Simplifying expressions involving Sum

I am trying to use Mathematica to simplify a symbolic expression involving Sum. Particularly, I define a sum via ...
587 views

### Need help with exception handling

I have read the docs for Catch, Throw, and friends multiple times, and I confess that I find them utterly incomprehensible... ...
328 views

### Conjugating symbolic expression

I am trying to conjugate a symbolic expression, and I have explicitly stated the real terms. However, I simply can't get it to work: ...
249 views

### Malliavin Derivative with Mathematica is it possible?

Is it possible to define a Malliavin calculus with Mathematica 9? Consider a random variables on the Wiener-space $\Omega=\mathcal{C}([0,1])$ of the form ...
202 views

### Errors importing UTF8 file to mathematica

I'm trying to import this file: Import["https://dl.dropboxusercontent.com/u/35192406/jarlaxxe_tweets.\ csv", CharacterEncoding -> "UTF8"] But I am getting ...
1k views

### Forecast Future Stock Prices - Brownian Motion - Again

excuse me, I think I have here a technical problem with Mathematica yesterday I posted the question with the title: Forecast Future Stock Prices - Brownian Motion I am still not very experienced but ...
103 views

### Some _atomic elements' TreeForm looks confusing with Level in appearance

In[1]:= Level[1/2,{-1}] Out[1]= {1/2} TreeForm[1/2] ...
281 views

### What causes strange line artifacts to appear in plots with certain PlotRanges?

I have seen this strange plotting artifact occur before and I was able to make it go away by changing the PlotRange. However, this time I need the prescribed PlotRange to be what I define and I get a ...
1k views

### ODE and BVP: NDSolve errors

The mathematical problem is shown here. I tried to solve writing the ...
428 views

### Use different kernels for different Notebooks

I know that the command LaunchKernels[] starts up four kernels on my machine: ...
250 views

### Autocomplete short symbol names in non-global context

Is it possible in v9 to autocomplete the short symbol names when one is operating in a context other than Global? I.e. after evaluating the following: ...
2k views

### NDSolve does not respond

For some sets of constants, NDSolve gives me true solutions, but when I try for example, T = 1/(2*2200), Mathematica does not respond. What can I do? The code below ...
199 views

### Dynamic application of several polynomials

I know how to get the 'resulting image' (y) from the application of a certain function (f) (here represented as the coefficients of a polynomial) over a certain interval (x): ...
585 views

### How to get the determinant and inverse of a large sparse symmetric matrix?

For example, the following is a $12\times 12$ symmetric matrix. Det and Inverse take too much time and don't even work on my ...
2k views

### Adding contour lines to a 3D plot?

I am having trouble getting contour lines on a 3D plot (ListPlot3D). I have tried ListContourPlot3D, but that gives me a really weird looking graph with a ton of dfferent levels. What I would like is ...
378 views

### How to change alignment of Grid/Matrix created using menu (Insert->Matrix/Table->New)

When I create a Grid using the menu, as follows: and then start to add data, I'd like to make the alignment to be left and not center which is the default ...
2k views

### Obtaining the Fourier transform of an operator

We know that if we have a function $f(x)$, and we call $g(\omega)$ its Fourier transform, then the Fourier transform of $x f(x)$ is $$\imath \frac{\mathrm{d} g(\omega))}{\mathrm{d}\omega}$$ and ...
3k views

### Plot Even Piecewise function

Is it possible in Mathematica to plot an even piecewise function like: $f(x) = \begin{cases} 3t , 0 \le t \le \frac{\pi}{2} \\ 3t + 6 , \frac{\pi}{2} \le t \le \pi \end{cases}$ which has ...
244 views

### Customizing FrameTicks in DistributionChart

So I have been fighting with this for a while. I'm trying to get custom frame ticks on both the left and right side of a DistributionChart. It's not going very ...
720 views

3k views

### DSolve gives complex function although the solution is a real one

I have a problem with the DSolve[] command in mathematica 8. Solving the the following 4th order differential equation spits out a complex solution although it should be a real one. The equation is: ...
770 views

### Converting a string containing whitespace-delimited numbers to a list of numbers

Suppose I have a string str that contains only whitespace-delimited real numbers: ...
3k views

### Passing a matrix as a function argument

I am trying to do the following: ...
4k views

### How to convert a system of parametric equations to a normal equation?

For example, I have a system of parametric equations (R is a constant number) : ...
3k views

### Calculating the distance between the coordinates in a list

I have a list of coordinates {{A[9, 4, 7], 0.0395174}, {A[1, 5, 0], 0.0163797}, {A[0, 7, 2], 0.0577425}, {A[2, 7, 5], 1.01313}} I want to find the distance ...
674 views

### Problem with Union and Intersection

Consider the following: list={{a,b,c},{c,d,e},{d,e,f},...{x_,y_,z_}}; I would like to apply Union on the elements of the list ...
96 views

### How many arguments does a function require, and how to use that in Manipulate

The goal is to vary the order parameters in wavelet transforms in the Manipulate environment. The various transformations have arguments of different rank. For ...
119 views

I have: ...
211 views

### Delete the white areas in GraphicsGrid

Let's see a simple example ...
297 views

### Working with derivative of conjugate of a complex number

I have a complex function, lets say $g(x)$. I want to take its and its conjugate's derivative. I need the solution of derivative which must be symbolically and computationally efficient. Lets take an ...
267 views

### Why do the eigenvectors for two similar matrixes differ by a large amount

I have two matrixes with values differs only slightly ...
209 views

### Fitting a rotated ellipse to data points [closed]

I have a bunch of x,y scatter data and I am trying to fit an ellipse through them. I understand that this question has been asked before and there are resources for this, e.g.: Fitting ellipse to 5 ...
177 views

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459 views

### How to implement the directed Barabasi-Albert algorithm in Mathematica?

Does anyone know how to implement an efficient version of the [directed Barabasi-Albert algorithm][1] in Mathematica that scales until hundred of thousands nodes? The directed network mechanism is ...
78 views

### Joint Distribution with a Constant

I would like to simulate from a joint distribution multiplied by a constant. e.g. 3*NormalDistribution[0,1]*NormalDistribution[1,1] I tried using something like ProductDistribution but that doesn't ...
156 views

### Include Formatting Save As .nb to .m

Is there a way to export Input Cells in my current notebook(.nb) as a .m file while including indents? For example if my notebook contains ...
173 views

### How can I determine Parameters for use in URLFetch`?

I'm trying to download data from website automatically using Mathematica, and URLFetch seems like it should be suited to the task. I'm interested in its "passing ...