2
votes
0answers
47 views

How to view an image from command line?

I'm running mathematica in command line mode, but I need to view a graph/image, so I'd like to open an image with an X11 window to inspect an image: Is there an easy way or built-in command to to ...
0
votes
0answers
28 views

NMaximize — Error + Output

When I run the code, Table[ NMaximize[ {f[α, χ, τ], 0 <= α <= 2 π, 0 <= χ <= π}, {α, χ}, WorkingPrecision -> 10 ], {τ, 0.1, 2, 0.1} ] ...
2
votes
0answers
49 views

Why FinancialDerivative fails for the Spread case?

According to the documentation center for FinancialDerivative in version 10.4, when there are multi assets, we still may use ...
2
votes
1answer
44 views

Interpolating functions and Look-up tables

This is just a general question about how InterpolatingFunctions work: If I have a complicated function that I don't want to have to evaluate many times over, does turning it into an ...
1
vote
1answer
114 views

efficient elementwise multiplication of SparseArray vector and matrix

I have a large SparseArray $P$ of dimensions $\{d,d\}$ and I want to multiply a vector (also a SparseArray) $v$ of length $d$ ...
0
votes
1answer
19 views

Element-wise SeriesCoefficient for matrix [duplicate]

I have a matrix expression which, when expanding with the Series[] command, returns $$\left( \begin{array}{cc} 1-\frac{1}{2}t^2+\frac{1}{8}t^4-O[t^5] & t-\...
1
vote
2answers
48 views

Merging Two Lists - Loops

I have 2 lists. For example, list1 = {{a,b}, {c, d}, {e, f}, {g, h}} list2 = {{1}, {2}, {3}, {4}} I want to merge them such that I get the result: ...
1
vote
1answer
64 views

Multiple curves plot from excel

I want to have a multiple curves plot which describes the energies of electron respect to distance. After importing data from excel, I have a table as below. The first row is the distances. Each of ...
0
votes
1answer
117 views

Solve returns empty list

I want to solve these equations but Mathematica gives no answer. ...
0
votes
0answers
31 views

Non commutative products and scalars

Say I have an expression such as $$a.(\alpha b)$$ where $a$ and $b$ are non-commutative operators, but $\alpha$ is simply a scalar. How do I tell Mathematica to treat $\alpha$ as a scalar and "pull" ...
0
votes
0answers
12 views

Help changing InputField value [on hold]

I'm not sure what I'm doing wrong since I've had this work before, but I have the user input a matrix using InputField, with initial values defined in ...
0
votes
0answers
40 views

How to delete sublist in a list?, with DeleteCase or similar

I like to delete the sublist that have the second element "" (or any other you can set as "-1" or "A") In the next example, I would like to erase the first and third sublist. How can I do this with <...
1
vote
2answers
76 views

How can I Plot DiracDelta function with complex number?

The function is: y[w_]= 0.32 DiracDelta[(2.495*10^-21 + 0. I) + 1.054*10^-50 w] + 1.19 DiracDelta[(1.979*10^-20 + 0. I) + 1.054*10^-58 w]; Question 1) ...
0
votes
0answers
35 views

How to change the output form of result

If you use Mathematica to do this integral: Integrate[1/(x^2 - a^2), x] you will get a uncommon function form like ...
2
votes
0answers
45 views

How to use notebooks on remote machines?

I need to use a notebook (the command line mathematica can't debug image stuff) and it has to be in EC2 (because of hardware needs). I managed to do this on a remote machine in aws using X11 windows ...
2
votes
2answers
112 views

Change bond cutoff distance when plotting .xyz files

When plotting a molecule from a xyz data file, Mathematica automatically adds the bonds between the atoms. But in my case it adds too many bonds, not only between nearest neighbours but also between ...
9
votes
3answers
261 views

Dataset collapsing/reducing

I have a dataset ds with 3 columns named A, B, C. Columns A and B have repeated values. How can I obtain another dataset that contains a list of the values in C for ...
7
votes
1answer
286 views

What are some useful (or hidden) properties of MeshRegion?

There is quite a bit of powerful functionality built in to MeshRegion, but it seems to be lacking in some areas. For example: extracting a list of edges that live ...
1
vote
1answer
77 views

Form with FormFunction problem

I've this form: f[a_, b_] := a + b; form = FormFunction[FormObject[<|"a" -> "Number", "b" -> "Number"|>], f[#a, #b] &]; form[] How I can ...
0
votes
0answers
7 views

Finding a closed form solution [migrated]

For the sequence 0 2 8 34 144 ... The recurrence relation is: $$\begin{align*} $E(n) = 4*E(n-1)+E(n-2)$ \end{align*}$$ How to calculate the closed form expression ...
0
votes
2answers
33 views
3
votes
1answer
89 views

Help with GeoRegionValuePlot

I am trying to get a map with 4 colors, I have several regions with values from 0 to 3 and I want to color those regions with value 0 in white, with value 1 in yellow, with value 2 in orange and with ...
0
votes
1answer
69 views

Improve speed of Nested Matrix exponential

I have a short Code example and I want to know whether it is possible to improve the speed. The L matrix in my code is a SparseMatrix, but for this question I just use something similiar. ...
3
votes
1answer
133 views

BoxWhiskerChart with logarithmic axes 2

I actually already found my answer on the question, however it is not working. see BoxWhiskerChart with logarithmic axes I want to create a boxwiskerchart with a logaritmic axes. But when I try <...
6
votes
4answers
290 views

Average dataset with many repetitions?

I have a dataset where each item is of the form: <|"p1" -> x1, "p2" -> x2, "r1" -> y1, "r2" -> y2|> The interpretation is this: ...
11
votes
3answers
1k views

How can I plot a loxodrome?

Can someone show me how to plot a rhumb line (loxodrome) in Mathematica via the ParametricPlot3D function? Here is what I got so far: ...
24
votes
2answers
1k views

Peirce's quincuncial projection

The Peirce quincuncial projection is the cartographic projection of a sphere onto a square. In short, I would like to see it implemented in Mathematica. Here is my code: ...
0
votes
1answer
62 views

Metric Simplify & grouping

I'm changing a basis from one metric to another. When simplifying the result Mathematica doesn't seem to grasp all the possible simplification: ...
0
votes
0answers
11 views

Logic or mathemathic sequence [on hold]

[10,2,4,6,2,8,5] Can someone tell me the logic behind this sequence? It was a question on a magazine without the last number - 5 - but i can't find any logic.
-5
votes
0answers
19 views

lyapunov versus coupling parameter [migrated]

i need a plot of lyapunov exponent versus coupling parameter graph for lorentz system.using the matlab program i got lyapunov versus time graph using programme below function ...
4
votes
0answers
53 views

Is every menu command equivalent to a command that can be executed within a notebook?

If so, is there a directory which gives the in-notebook command associated with each menu command ? In particular, I would like to know how to replicate the menu command Evaluation -> Quit Kernel -> ...
0
votes
0answers
35 views

Part command in a matrixform [duplicate]

I do have a MatrixForm a table which I would like to pick just a part of it. Is it possible to somehow command part[[]] for a <...
-1
votes
0answers
26 views

Please check my code for gauss elimination and rectify the mistake [on hold]

clc; clear all; prompt = 'Enter No of Unknowns \n' ; m = input(prompt) ; a = zeros(m,m) ; x = 0 ; for x = 1:m for y = 1:m prompt = 'Enter element(x,y) \n' ; ...
3
votes
3answers
145 views

How do I define a two point random variable?

How do I define a random variable $X$ such that $Pr[X=x_1]=p_1$ and $Pr[X=x_2]=p_2$ where the values $x_i$, $i=1,\,2$ are just symbols and the probabilities $p_i$, $i=1,\,2$ are symbolic expressions ...
0
votes
0answers
27 views

Using RegionFunction with non-trivial Inequality

So I have been using ContourPlot to plot the zero set of a fairly unwieldy function, with many intersecting components. There's really only one of these components ...
4
votes
1answer
68 views

How to access box-and-whisker specifications from custom ChartElementFunction?

I am creating a custom ChartElementFunction for BoxWhiskerChart. I would like to access the box-and-whisker specifications from ...
0
votes
1answer
37 views

Problem with “FrameLabel” when specifying Superscript, Italics, and Times (font)

I'm using FrameLabel to create the label "ln p'(t)" [which is, natural log of the function p'(t)]. This is to be publication quality, so I specify Times font, and Italics (see below). But the "prime" ...
10
votes
1answer
109 views

Bug with Compile and Log2?

It seems that Log2 in Compile gives numerical errors (CompiledFunction::cfn) if the input is ...
0
votes
0answers
24 views

With regards to the LogLogPlot on Wolfram alpha [on hold]

I plot Logplot for a function , it comes out nice, however when I plot the log log one, it doesn't work, Here are the images. Can someone tell me what's wrong here.
6
votes
3answers
88 views

How to create a window which will close in a certain amount of time?

I'm currently making an interface in Mathematica and I'll need to bump a window out and then let it close itself in a certain amount of time. Here's an short example to illustrate the effect: ...
0
votes
0answers
32 views

Solving Inequality with Exponentiation and Log [on hold]

I have an inequality that I am not able to proove which is $Log[d] <\frac{(-1 + d^M) (d^M - d^N) N} {d^{M}(-1 + d^N) M (M - N)}$ with $0<\delta<1$, $M\geqq1$, $N>M$ and thus $N>1$. I ...
0
votes
1answer
38 views

Troubles with showing axis after saving in EPS

I'm trying to save a picture in EPS and then to put it into my LaTeX document. But when I put it the left axis is not shown. How do I fix it? (look at the screens) If I save the image in JPG, there'...
3
votes
0answers
24 views

Weird bug with Esc, string, and underscore?

There seems to be a bug with esc key, strings, and underscores. For instance, see the following code: a = f["1_2"]; If an esc character is typed anywhere ...
1
vote
0answers
38 views

Inverse Laplace Transform Failing: $\frac{1}{\exp (\beta \tau )-a}$

I have tried various approaches to get the solution to this inverse transform but all so far are failing. ...
1
vote
0answers
29 views

3DPlot, Logarithmic x and y axes, Interpolating function

I've used NDSolve to get an InterpolatingFunction that solves a certain difeq. I want to see the behavior of this function on a couple different scales, so I want to use some sort of Log Plot. For a ...
0
votes
0answers
25 views

Error of $Failed when defining a function [on hold]

I am trying to define the function below. K[r_, a_] := -((a (3 + 2 a r^2))/(1 + a r^2)^2) Thus far, I have gotten the error ...
1
vote
1answer
87 views

Asymptotic solution

I have an ODE V''[z] + ( (I z0^2 w)/(3 (z - z0)^2) + (2 - (4 I z0 w)/9)/(z - z0)) V'[z] + (-(12/41) I z0 w + (23 z0^2 w^2)/369)/(z - z0)^2 V[z] == 0 ...

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