All Questions
91,384
questions
0
votes
1
answer
28
views
Finding the maximum of a equation
Hi guys I have the following function
$R_t = \exp(-2 k_x^2 \sin^2(\frac{t}{2})) k_x^2 \theta(t) \bigg[ -\sin(2t) - \sin(t) (1 - k_x^2 \sin^2(t)) \bigg]$
and I want to find the maximum value of it.
I ...
- 157
2
votes
1
answer
37
views
Generate all possible lists of integers that match a pattern
I have a pattern defined using variables: {a,b,a,b} and I want to generate all possible instances of this list where each variable ranges from 1 to n, and each ...
- 87
5
votes
10
answers
106
views
How to write a duplicate mapping function?
I need a function MapDuplicate that maps a function on all the duplicates in a list.
Consider the following list:
...
- 9,023
0
votes
0
answers
33
views
How to solve quartic equation modulo a composite?
I have an univariate polynomial equation over a composite moduli.
Namely the composite is of for $q=(2p)^{2}-1$ where $p$ is odd and $2p-1$ and $2p+1$ are distinct primes.
The modular equation is
$$ax^...
- 135
0
votes
0
answers
30
views
BooleanConvert: Boolean decision tree
The BooleanConvert function includes an available form called "Boolean decision tree": BDT.
What is the formal logical definition of a Boolean decision tree as used here?
What is the ...
- 440
0
votes
0
answers
57
views
How to return only the negative complex solutions of DSolve or using FindInstance
I am using DSolve to find the solutions to two differential equations. The problem is from the first solution, I only want the solution that includes a negative ...
- 101
0
votes
0
answers
44
views
Solving a linear algebra problem involving minimal polynomial degree
Consider a set of three-dimensional points ${\left\{{\left(a,b,abc\right)}~\middle\vert~a,b,c\in\mathbb{N_+}\land a+b+c\leqslant2023\right\}}$. If there exists a non-zero real polynomial $\...
- 375
4
votes
5
answers
159
views
Extract data from ragged arrays
I have data in ragged arrays of the form
$$\left(
\begin{array}{cc}
\text{x1} & \{\text{a1}\} \\
\text{x2} & \{\text{a2}\} \\
\text{x3} & \{\text{a3},\text{b3},\text{c3}\} \\
\text{x4} ...
- 16k
-3
votes
2
answers
170
views
Solving $2^a - 2^b = 2^x$ for extremely large $a$ and $b$ [closed]
I want to solve the equation
$$2^a - 2^b = 2^x,$$
where $a$ and $b$ are extremely large numbers, for example $a =10^{10000 G}$, $B=10^{100G}$ with $G=10^{10^{100}}$, and I don't want to calculate the ...
- 103
1
vote
3
answers
83
views
Converting two 8-bit integers into a single 16-bit integer
I have a situation where I have a pair of integers {a, b} where a and b are in bytes from a ...
- 63
0
votes
0
answers
53
views
How to create an n-by-1 matrix from user-input values? [closed]
I want to create a n-by-1 matrix for any n inputed by the user. Also the elements in the matrix should be entered by the user.
4
votes
4
answers
216
views
An accumulated moving average
1. Problem statement
In accordance with the standard definitions the inbuilt MovingAverage
...
- 40.4k
1
vote
2
answers
107
views
How to calculate the depth of the lake in mathematica?
I want to calculate mean depth of Goose lake (mean depth=4.6 m), I use bellow command for this operation, But this command is not automatic and we have to create the coordinates manually, and on the ...
- 137
0
votes
0
answers
34
views
Hiding Initialization Cells
I have seen multiple notebooks with near invisible Initialization Cells, and wish to recreate them myself (see screenshot below).
In the screenshot, the first Initialization Cell is expanded, ...
- 105
1
vote
0
answers
42
views
Using Local LLM Service That Duplicates Open AI API
I have a local service running on https://localhost:PORT/v1 that duplicates the Open AI API functionality available at ...
- 1,394
3
votes
2
answers
150
views
How to Draw Rectangle Chart Using Three Layers of Data?
I have some data given at three levels:
...
- 5,303
1
vote
1
answer
70
views
Post Processing of Solution and Plot of Coupled Partial Differential Equation Over a Semi-Circular Domain
Linked Question: Solution and Plot of Coupled Partial Differential Equation Over a Semi-Circular Domain.II
Many many thanks to @Nasser (https://mathematica.stackexchange.com/users/70/nasser) for his ...
- 87
2
votes
1
answer
88
views
Finding zeroes of a modified Bessel function of the second kind
Let
$$
f_n(\omega):=K_{i \omega}(2\pi n)
$$
with $\omega>0$, $n=1,2,\ldots$ and $K_{\nu}$ a modified Bessel function of the second kind.
For each fixed value of $n$, $f_n(\omega)$ has an infinite ...
- 585
1
vote
2
answers
78
views
Finding the maximum amplitide quantitatively using interpolation
I have the following table
data = Table[Sin[i], {i, 0, 10, 0.1}] // N
And I plotted the data as follows,
Now I want to know the value of each maximum with high ...
- 157
0
votes
1
answer
56
views
Plotting Using Nesting Manipulate
My goal is to plot the number of locatable points and their average point as fig2. The number of points is set by the slider and they are locatable. My code with nesting Manipulate is as shown below, ...
- 265
0
votes
1
answer
42
views
Showing that the difference between two CDF functions is positive when CDFs are symbolic expressions
I'd like to check the sign of a symbolic expression conditional on some predefined assumptions. More specifically, first, I want to assume that the mean and variance of a normally distributed random ...
0
votes
2
answers
38
views
Interpolation function for data with repeating independent variable
I want to find an interpolation function for data in which the x-variable is repeated (example below). The repetition in data is natural and cannot not be eliminated.
Can I somehow use ...
- 307
1
vote
2
answers
69
views
Mapping from n-sheeted Riemann surface to the complex plane
Reading about conformal field theories in two dimensions, I run into the following statement needed for a demonstration:
Consider an $n$-sheeted Riemann surface with branch cut along (0,$\infty$. This ...
- 11
4
votes
4
answers
143
views
How to check if at least one ordering of the given row matches one of the rows of a table?
Consider some list of elements
...
- 4,984
2
votes
4
answers
199
views
How to check if the given row matches one of the rows of a table?
Consider some table
tabb = RandomInteger[{0, 4}, {5, 4}]
and a row
row = RandomInteger[{0, 4}, 4]
How to check if ...
- 4,984
4
votes
1
answer
135
views
Select a specified subset of vertices distributed on a circle
A circular embedding is a graph embedding in which all graph vertices lie on a common circle, usually arranged so they are equally spaced around the circumference.
If I only specify that some of the ...
- 1,851
0
votes
1
answer
53
views
How to give conditions and solve an integration?
I want to solve an integration,
$\int \frac{da}{\sqrt{\frac{8 \pi G \Lambda}{3}a^2 - K +c_1 a^{-(3k+1)}}}$
Here, how to give conditions k $\ge$ 0, G$>$ 0, $\Lambda$ $>$ 0 and K can be zero, ...
- 307
0
votes
0
answers
77
views
Is there a way to optimize it for larger n?
This is Domen's code from my previous thread here. I think it covers all the cases that I mentioned there and works well for small values of n. However, for large ...
- 2,361
0
votes
1
answer
42
views
About using series function
I am using Series function on (1/z)(-k^2)^z. Up to z^0, the function gives me 1/z + Log[-k^2]. But in the standard textbook on QFT, it turns out the expansion should give 1/z + Log[k^2/mu^2] -i*pi up ...
- 19
6
votes
2
answers
321
views
Tomographic Reconstruction of a Convex Polyhedron from its Orthographic Projections
So, I can construct a random polyhedron and find its 3 silhouettes onto the 3 standard planes.
For example,
...
- 445
1
vote
2
answers
58
views
Conjugate symbol
Is there a way to make mathematica display Conjugate[z] as z* or something like that? It gets very verbose when there are multiple conjugates in an expression, it becomes hard to read.
- 1,243
1
vote
1
answer
34
views
Manipulate: How re-initialise the initial value of a dependent PopupMenu driven by another PopupMenu?
Using Manipulate, I would like the items offered in a 2nd PopupMenu to be driven by a 1st PopupMenu. I can get the dynamic driving of the offered items working, but not the initial value of the 2nd ...
1
vote
0
answers
27
views
Performance of DensityPlot3D with non-opaque Graphics3D
Does anyone have problems with performance of graphics combining DensityPlot3D and any other non-opaque Graphics3D? If I combine ListDensityPlot3D (very simple one, first from documentation) with only ...
- 392
1
vote
1
answer
51
views
Keywords included in most sentences in a paragraph?
I created a few functions that will retrieve some text from certain medical articles. However, not all articles are useful or even match the keywords I provide. Is there a way to "grade" ...
- 159
0
votes
0
answers
54
views
Stiffness or singularity in NDSolve for a system of equations with switchpoint
I am trying to solve the following set of equations:
...
- 73
6
votes
1
answer
95
views
Getting Area from GeoGraphics
I want to find the area covered by the reservoir of a dam using a satellite image.
This is what I have so far.
...
- 79
2
votes
1
answer
100
views
Solution and Plot of Coupled Partial Differential Equation Over a Semi-Circular Domain.II
This question is connected with reference to my previous question (Solution of Dimensionless Partial Differential Equation Over a Semi-Circular Domain), where I asked for a help to solve the following ...
- 87
0
votes
2
answers
94
views
Why can't NSolve find values that FindInstance can?
I am trying to solve for \[Epsilon], given three input paramters n, x and ...
- 376
0
votes
0
answers
43
views
Why does the string "\" prevent a graph6 string conversion to a graph?
I input the graph6 string ...
- 1,851
2
votes
1
answer
120
views
Recurrence formula evaluating with speacial counting of subscripts
Hoping to check some recurrance relationship like this
$a_1 = x$ and $a_2 = y$, with
$$
a_{2n+1} = a_{2n} a_{2n-1}
$$
and
$$
a_{2n+2} = a_{2n+1} + 4
$$
Tried
...
- 1,460
2
votes
1
answer
85
views
How can I use UpSet with a derivative value?
I'm trying to UpSet a certain value for the derivative of a function $Y=Y(l,m,x)$.
This can be done by:
...
- 612
0
votes
0
answers
37
views
Plotting the energy density of Gravitational Waves
Is there a way to reproduce the curve of the spectral energy density of the Gravitational Waves in Mathematica, Figure (1) in : 0703290. It is given by Equations (63) and (64).
- 335
1
vote
2
answers
83
views
Can you recover the original vectors that, when summed together, achieved a particular criteria
I am wondering if it is possible to take the binary strings of length $3$ (tuples) whose sums have weight $2$ (i.e they have $2$ non-zero entries)(binary case, meaning they have two $1$'s entries) $$u ...
- 417
3
votes
2
answers
110
views
Represent data as a table with diagonally split color-coded cells
I have two rows of values that I'd like to represent as a table, where cells are diagonally divided showing color-coded values with column A and column B values for each row such as below:
Any neat ...
- 301
0
votes
0
answers
21
views
Opening of help web hesitating few seconds
I do not have documentation stored on my PC to save some space on HDD.
When I want help on some function I type its name and press F1 and online documentation of ...
- 7,044
4
votes
8
answers
449
views
Delete list elements above a certain threshold
1. Problem statement
Going from right to left, I want do delete all elements after they have occured n times. The solution I found seems to work reliably, but is ...
- 40.4k
1
vote
0
answers
37
views
Parametric Plotting 6D dimensions to 3D for Visualizing a Solution
I am trying to find out when: $$f(x,y,z,α,β,γ):= zcos(β)cos(γ)+y(cos(γ)sin(α)sin(β)+cos(α)sin(γ))+x(−cos(α)cos(γ)sin(β)+sin(α)sin(γ)),$$ where $α,β, \text{and } γ$ can be any value in $[-2\pi,2\pi]$ ...
- 445
1
vote
2
answers
120
views
Integral convergent or divergent?
How can I find out for what values of r (both lower and upper limits), is this integral convergent/divergent?
...
- 343
1
vote
2
answers
63
views
1
vote
0
answers
48
views
Why this code does not show three legend lines?
My code shows empty legend lines. What should I do to show the graph with three legend lines?
...
- 11