# All Questions

348 views

### How to obtain transparent animated gif via Export?

I have the following code to create animated GIFs: ...
66 views

### Why does Repeated not work in this case?

I think I don't understand how to use Repeated. I have a list for example list={a,b,a,b,a,b,a,a,b} I want to detect whether ...
123 views

### Interesting “Tuples” application

I want to start with: {a,b},{c,d},{e,f} and end up with: {a,c,e},{a,c,f},{a,d,e},{a,d,f},{b,c,e},{b,c,f},{b,d,e},{b,d,f} ...
100 views

### Fourier transform of Exp[x]/x

Could you please explain why Mathematica gives the following expression when taking Fourier transform of $\exp(\lambda z)/\lambda$? $$\frac{-\log(-z)+\log(z)}{\sqrt{2\pi}}$$ Why the answer does not ...
29 views

### FindRoot outputs a lot of nlum and ReplaceAll errors before outputting (close) root

I'm trying to find the root of the root function when some other variable is subtracted. I.e. FindRoot[root[theta, r, h]-H, theta] Whenever I do this, FindRoot ...
42 views

### check content of a Matrix

I have a matrix which contain rotated ellipses and points, how can I check if the element in the position {i,j} is either a point or an ellipse? the code is a bit longer but the structure is like: ...
42 views

### Evaluating Root forms in a Table

When I put a Root form in table, the parameters of the Root form don't evaluate. I don't know how I can indexed values substituted into root form in the table to get have numeric output. ...
65 views

### How to make a set of interdependent popup menus work?

Here is my code that is not working. ...
106 views

### Arithmetic Progression [on hold]

How can I resolve these issues? I'm from Brazil and I don't have many things related to the subject here ** In an arithmetic progression of 6 Terms, the reason is 5. The product of the 1° with the ...
36 views

### “Not enough memory” error even though plenty of memory still available

Summary: The evaluation of an Export[...] expression fails with a "Not enough memory available" error, but the value returned by ...
90 views

### Multiple output cells, suppressed by semicolon

I'd like to write a function that outputs multiple cells, as in Multiple output cells, but not when the function is called with a semicolon at the end. Any idea how?
561 views

### Row-Reduced-Echelon-Form with Equation Parameters for Consistent Systems

I often do row-reduced-echelon-form (RREF) calculations that involve parameters using the RowReduce command. Most times, I want to know which parameters make the system consistent. For example: ...
46 views

### Fastest way for data input into StreamPlot function

I'm interested in looking at graphing the phase portraits of 2x2 autonomous ODEs, and I'm using the StreamPlot function. Here is one simple example: ...
74 views

### How to convert Image3D object into Graphics3D object and vice versa?

There are some rendering options (for example, Lighting) which are associated with the Graphics3D objects. I cannot apply these ...
96 views

### Finding negative sequences in a large list: optimization

I ran across an interesting challenge recently, and I was thinking this community would know how to optimize it. I have several data sets which have (currently) about 50k-100k points. The sets ...
60 views

### Dialog notebook with multiple popup menus

I'm trying to create a user interface in Mathematica; the user will enter specified information, it will be processed, and then data will be inserted into a MySQL database. The pieces work ...
125 views

### Solving system of equations with (nested) Bessel Functions

I'm trying to find solutions to a system of equations which include Bessel functions. It feels like the problem for mathematica is that the arguments of the Bessel functions are functions themselves ...
96 views

### How to convert arbitrary raw boxes directly into String?

This question is motivated by the recent question about searching inside of the NB files. According to the Documentation, ToString expects a high-level WL ...
30 views

### Is there a syntax coloring type that highlights only when not in a list?

How do I define the syntax coloring of function myfunc so that it only colors the variable that is not in a list? For example, ...
65 views

### Nonlinear Markov chain (numerical simulation)

Suppose you have a linear Markov process, and you can write it as x(t+1) = Ax(t). Here x is the vector of values, and A is the transition matrix. Since this is linear, it can be solved analytically, ...
37 views

### Can “Part” be hold? [on hold]

I'm trying to define a function of which the length of the argument is undetermined. However, the exact form of this function depend on the length of the argument. And to save time, I have to evaluate ...
35 views

### How to call a function with an arbitrary list as its arguments inside a functional? [duplicate]

I have the following functional defined (i.e. a function of another function) where variableList contains the variable (arguments if you wish) of the ...
25 views

### What mathematica function to identify/approximate branching model\ [on hold]

I have a class of problems illustrated by the example below with emphasis on the fact that the sum of the variables is a constant. Is there a name for such problems? Which mathematica function would ...
88 views

### ListContourPlot cannot plot enormous datafile [on hold]

I would like to create a ListContourPlot from a list with about $7,000,000$ triplets (x,y,z) using the following code: ...
4 views

### Isothermal coordinates [migrated]

Is there an application or interest in studying the isothermal surfaces where the metric is $ds^2=E∗(du^2+dv^2)$ and where $E>0$ is an harmonic function? I know that this metric is a special kind ...
46 views

### Use If condition with ListPlot

Here is my code to use If condition with PLot: ...
38 views

### Moving label with manipulate [duplicate]

In the following Manipulate, I would like to plot a distinct comment in each distinct zone which will move with the manipulation. Is it possible ? ...
171 views

### OEIS A144311 Generating function

I'm looking for a way to use calculate OEIS A144311 efficiently in Mathematica. First, let's define the series. In one sense or another, this series considers the number between "relative" twin ...
43 views

### How to arbitrarily label the points in ListPointPlot3D within Manipulate?

I want to label the points displayed in 3D within a Manipulate expression with arbitrary text. My code is as follows: ...
66 views

### FunctionInterpolation produces many error messages when given high-precision input [duplicate]

Both FunctionInterpolation[1, {x, 0,1.00000000000000004}] and FunctionInterpolation[1.00000000000000004, {x, 0, 1}]; ...
430 views

### Permanently rounding numbers/values to a given number of significant figures

I am searching for a simple way of rounding and setting an input to a desired number of significant figures. There are a vast number of posts that discuss similar problems, but none address this ...
8 views

### ALS Matrix Convergence [migrated]

I came across this statement in some MapR documentation on ML in Spark: ALS is an iterative algorithm. During each iteration, the algorithm alternatively fixes one factor matrix and solves for ...
491 views

### A problem about function N

Toady,I have a problem about N,described as below: For example N[1/3, 5] (* ==> 0.33333*) and ...
49 views

### Solving and Plotting Infinite sums over solutions to transcendental equation involving Bessel functions

I am trying to use Mathematica to plot the following equation $E(q,\Delta)$ vs $qa$, for set values of $D \Delta/a^2$ and $\bar\rho a/D$. I have looked at other stackexchange posts which deal with ...
36 views

### Why doesn't N[0.33333, 3] return 0.333? [duplicate]

Basic question, other answers I found didn't really seem to address this. N[x,3] seems to only work if x is analytic instead of ...
20 views

### How to fit small squares in the big one? [on hold]

Suppose, I have a square S with height H and width W. Also I have another square ...
70 views

### What options for project development exist if the Cloud and Mathematica Online cannot be used

Due to contractual obligations to protect IP and client information, we unfortunately, cannot use Cloud or Mathematica Online for development in the development of our projects. We are further ...
20 views

### Getting just a number out of a list [on hold]

Witht the command dummy1 = Position[Subsets[Range[n]], {3, 4, 5}] I am getting a list of the form {{26}}. Is there any way to get just the number 26 as an ...
63 views

### Moving a plot label along with a moving threshold line

Here is a simple Manipulate expression with a threshold. ...
42 views

### Get asymptotic form of a Legendre function expression [on hold]

How to get the asymptotic expression of the first element of the following list with small x and very large n? ...
21 views

### Defining a differential form in the Exterior Differential Calculus package [on hold]

I want to define the following differential form $\qquad F = H^{01} dx \wedge dt$ However, when I type F = H^01 d[x]⋀d[t] I get the error Recursion depth ...
66 views

### Solve equations with Monte Carlo

I am dealing with a complicated problem. I will use a simple problem to explain it. I have two variables x and y, and two equations: x+y=A 2x+y=B The value of A and B is determined by measurement, ...
156 views

### planar Conic Sections plot

Among answers of ConicsAssemblyQuery, I posted images that are not pretty. In particular, the parabola is elusive due to large parameter step. Please help. The program attempts to translate and ...
1k views

### Does Mathematica have a built-in date picker?

Does Mathematica have an interactive date input control that lets the user choose a date by browsing to a calendar view and returning the selected date as a date list? For example, something like the ...
300 views

### Can your Mathematica do the following integral?

Backslide introduced in v10 and fixed in v10.4.1. I was trying to do the following integral in Mathematica: Integrate[(z-2) PolyLog[2,z]Log[1-z]/z^3,z] What I ...
160 views

### How to speed up Integration of interpolation function?

I have a list of data, and I interpolate it to a function. Then I need to do an integration with the interpolating function. But I found that the speed is unacceptably slow. My data is here (a little ...
3k views

### Convert spectral distribution to RGB color

Presume that I have a spectrum as a function of wavelength (an example being the blackbody spectrum): I want to convert that to a single RGB color to display on-screen, i.e. the "color" of that ...
303 views

### How to use Get on a folder

In the documentation for Get it says: If the file found by <<name is a directory, the Wolfram Language will try to ...
I have a MIMO TransferFunctionModel and what I would like to do is get the transfer function of $j^{th}$ output to $i^{th}$ input. I just want to access this particular transfer function and do ...