# All Questions

362 views

### Erfi[z] expansion in Mathematica: is this a bug?

Looking at the expansion: Series[Erfi[x], {x, Infinity, 1}] I obtain -I+E^x^2 (1/(Sqrt[\[Pi]] x)+O[1/x]^2) (note the ...
116 views

### Incorporating a Manipulation in an Animation

I am having trouble incorporating a manipulation into my animation. I want to be able to maniuplate the 5 constants at the beginning. Am I going to need to combine all of the code into one string? ...
101 views

### Replace inverse function

I'm solving an expression like so: Solve[u[x] == u[a] + u[b], x] Mathematica returns {{x->(u^(-1))[u[a]+u[b]]}} If I ...
70 views

### Is it possible for Mathematica to give the step by step process of Reduce command? [duplicate]

Input: Reduce[3 x^2 - 2 a x + a^2 - 1 >= 0 && x > a, x] // TraditionalForm Output: ...
197 views

### Autoupdate Dynamic Variable and Selectable

Does there exist a technique to construct a Cell that allows you to both auto update a Dynamic variable and allows you select the code while the variable is being ...
217 views

### singularity in NDSolve for some values of parameter

my equation is: ...
224 views

### Key to get help about current function

I know you can hit F1 to pop up the documentation center, and then type the name of a function and search for it. I'd like to know if there's a key that just pops up the help page of the function ...
449 views

### ListPlot under conditions

I have a data file containing several columns and thousands lines of data. Below I present a small portion of it, in order to express my issue: ...
1k views

### Simplifying expressions with square roots

I would like Mathematica to simplify this expression: $4 \left(16 \sqrt{\left(-1+2 c^2\right)^2}-32 c^2 \sqrt{\left(-1+2 c^2\right)^2}+\sqrt{\left(1-8 c^2+8 c^4\right)^2}\right)^2$ ...
342 views

### Randomness test suites that can be invoked from Mathematica

There are several test suites referenced at csrc.nist.gov designed to test a (pseudo-)random byte sequence for randomness, and discover possible skews, correlations, patterns, or other hidden ...
242 views

### Is it possible to separately call the default value of a variable which isn't at the end of the sequence?

After reading this post I recalled an old question I once met. We know that we can set default values for variables of a function: ...
255 views

### Error while exporting to Excel with named sheets

Using Mathematica v9.0.1 This example is from the docs: ...
127 views

### How can I export definitions of several symbols to a single file?

the problem related to this question What I want to do is to Export definition of several symbol into a single file. The reason I choose ...
255 views

### Utterly confounding behaviour in Mathematica 9 DSolve

I've been baffled by a lot of the behaviours of Mathematica 9 — so much that I regret upgrading my copy of Mathematica 8 (I would downgrade but I'm currently on vacation). Here is an example: ...
138 views

### How to simulate a multivariate recursive system from a list

New to mathematica, trying to use Eric Swanson's Pertubation AIM program to solve DSGE models. His code produces a solution as a list or a table. My question is how do I use this list to simulate the ...
515 views

### Drawing dessins d'enfants (bipartite graphs subject to certain conditions)

I want to write a function which constructs all possible dessins d'enfants (bipartite graphs fulfilling certain criteria, given below) from a collection of data presented in the following form: ...
372 views

### Mathematica inserts extra \left and \right for absolute values in LaTeX output

Type the following in a Mathematica DisplayFormula cell(other styles may also encounter this problem): Esc+l+|+Esc and Esc+r+|+Esc, and save as LaTeX. Note: See the difference of the character ...
235 views

### How to fold output cells by default?

In Mathematica the default behavior of output cells is to pop up after the kernel has processed the input cells and got a result. I know I could add ; in the end of ...
332 views

### Color inversion using ArrayPlot

I have a 3D data that I want to visualise its each slice with ArrayPlot. However, there is a problem the way it represents the data. As, ArrayPlot by default generates grayscale output, in which ...
132 views

### Restrict MousePosition to specific Graphics object

I have a problem using MousePosition. I want to restrict the value returned by MousePosition to a specific Graphics object. ...
164 views

### HTML documentation build issue with Wolfram Workbench 2 and MMA 9

Using the Wolfram Workbench 2 (and Mathematica 9) to build HTML documentation for a package I am developing, I am ending up with HTML pages that contain a lot of text elements that look like this: ...
195 views

### Style markers in strings

I'm dealing with strings in Mathematica and I would love to handle their stylling in the most cenvenient way. Without loss of generality, let's assume I want to make some parts of string ...
228 views

### Save as Tex $$\(f(x))$$\) double \('s problem

a simple example Text Cell Style with a inline Cell (DisplayFormula) ...
937 views

### The underlying process of Integrate[] [duplicate]

Integrate[x^4 E^-x^2, {x, 0, +∞}] Output: (3 Sqrt[π])/8 Can someone explain to me the specific calculation process ?
161 views

### Is it possible to use some short form in Postfix

example 1 we can use Information , but can not use ? Sin // Information Sin // ? ...
153 views

### Using Select on list of vectors [duplicate]

I have a dataset, where each element in the list is a vector as in data = Table[{i, 2 i, 3 i}, {i, 1, 10}] As an example, I am interested in the entries where ...
923 views

### Data Table Manipulation in Mathematica: Step 2

In this previous post (Data Table Manipulation in Mathematica) we find the brilliant suggestion proposed by Leonid Shifrin that allows to select specific rows identified by the header name. I'm now ...
348 views

### Symbolic integration fails while numerical integration succeeds

I am hoping to evaluate the following integral Integrate[((r^3 - 7)^(2/3)*(1 - (r^3 - 7)^(2/3)/r^2))/r^3, {r, 2, Infinity}] but Mathematica informs me that this ...
461 views

### How does Return work?

It is not completely clear to me how Return[] works. The documentation says: Return[expr] returns the value expr from a ...
913 views

### How does Plot work?

I considered the following function: sin[x_] := Module[{}, Print["x=", x]; Sin[x] ] in Mathematica. Next, I tried to plot it using: ...
643 views

### How does Mathematica determine that an evaluation should be terminated?

How exactly does Mathematica determine that evaluation of particular expression should be finished and the result should be returned? Here are some examples of unclear behavior which have arisen, ...
1k views

### The clearest way to represent Mathematica's evaluation sequence

WReach has presented here a nice way to represent the Mathematica's evaluation sequence using OpenerView. It is much more clear way to go than using the standard ...
1k views

### Replace inside Held expression

I wish to make functional replacement inside Held expression like this: ...
174 views

### The Flat Attribute, Unevaluated and the Evaluation Process

To make this question easy to follow let's give some symbols a couple attributes. Attributes[f] = {Flat}; Attributes[s] = {Orderless}; Now consider the ...
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(My code:) ...
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### How to make a conditioning plot?

I'd like to make a conditioning plot just like coplot in R. Is there a pre-made solution or do I have to make a bunch of plots individually? Edit: This is an example from r screenshots. It is a way ...
59 views

### Export and Import with graphics characters

I exported a list of characters say: Export["hello.txt", {t, r, $\theta$, $\phi$}, "List"]; the file has the correct symbols when opened with a text editor, however, when I imported it with ...
120 views

### Evaluation of elements in a list and then sorting them

This is probably a simple problem, but I'm having a lot of issues with it because I'm unfamiliar with Mathematica syntax. I have a list ...
537 views

### Generating a “best fit” curve to a set of noisy data corresponding to a moving object

Please note that this is an extension of a previous question: Interpolating a sparse list of two-dimensional coordinates We have an ordered array of coordinates corresponding to the position of an ...
243 views

### Partitioning a superset of coordinates into subsets that generate continuous curves

Consider the data set corresponding to recorded trajectories for a particle: ...
184 views

### Series resulting in “No more memory available.”

Is there any way to force Mathematica to come up with the closed form to Sum[1/(i^18 (i^2 + j^2)), {i, 1, Infinity}, {j, 1, Infinity}] or ...
194 views

### Interpolating a sparse list of two-dimensional coordinates

I've run into a problem where I have an ordered array of sets of coordinates, for example: ...
445 views

### Problem with Fourier and InverseFourier function

I have the following code Image[img, ImageSize -> 300] data = ImageData[img]; fdct = Fourier[data] tdata = InverseFourier[fdct]; Image[tdata] but it seems to ...
1k views

### DSolve doesn't find a solution

I have this partial differential equation (G and M are constants): and a solution is: Mathematica doesn't find any solutions. My code for DSolve is: ...
6k views

### How do I save a variable or function definition to a file?

Is it possible to save a function which was created via Interpolation of some data in such a way that I can use this function in a new Mathematica session without ...
230 views

### Defining a polygon by clicking on an image [duplicate]

Imagine I have some image, $I$, and I'd like to define a polygon by sequentially clicking on the image to define vertices $(v_1, ...) \in V$, where vertices $v_i$ and $v_j$ share an edge if \$j = ...
5k views

### How do I identify the source of a “Tag times protected” error?

I have some code that looks like Table[ a = 1; b = {2, 3} c = i;, {i, 2} ] which gives an error: Set::write: Tag Times in c {2,3} is ...
397 views

### Temporarily redirect the output of Print[ ] to a second file

I have started using Mathematica to automate file backup operations. The logistics I need make Mathematica a good choice. I am testing and developing the Notebook manually, and ...