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Recovering formulas for sequences with integer coefficients

Suppose I know the sequence is of the $a n^4 + b n^3 + c n^2 + d n$, with positive integers $a,b,c,d$, what is the easiest way to get them from the first few coefficients? Here are the sequences I'm ...
Yaroslav Bulatov's user avatar
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0 answers
15 views

Destructuring the left-hand-side of `Optional[s:v]`

It is useful to be able to provide default values in pattern-matching, for example, if an element has a key but no corresponding ...
Diffycue's user avatar
  • 1,773
0 votes
0 answers
7 views

ComplexRegionPlot - Plot transform of z

Using ComplexRegionPlot, how can I please plot a transform/function of the input variable $z$? As an example, considering $(*)$ ...
Sinistrum's user avatar
0 votes
0 answers
11 views

Manual updating of function in Do loop

Previously I had asked a question about solving Maxwells equations with boundary conditions, here Machine overflow when defining boundary conditions. I have managed to successfully run the code ...
Jole Stock's user avatar
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0 answers
20 views

Clarification of copyright in submissions to Wolfram Function Repository

the DATA repository has a statement here ... https://datarepository.wolframcloud.com/submission-agreement but what about FUNCTIONS? Does 3rd party use include (say) compiling the source into another ...
Richard Fateman's user avatar
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0 answers
24 views

Fitting delay differential equations (DDE)

I have the following differential equations: $$S'(t) = 0.31 S(t) \Big( 1 - \frac{S(t)}{6.19} \Big)- \frac{a}{1 + B(t)} S(t),$$ $$B'(t) = c (1 - B(t)) - d B(t) S(t) - 3 c (1 - B(t - 18)),$$ where $B(t -...
Tim's user avatar
  • 41
0 votes
1 answer
22 views

How to reproduce Eugen Jahnke's drawing of a complex function

Eugen Jahnke (1863 - 1921) studied mathematics and physics at the Humboldt University of Berlin, where he became a professor at the Mining Academy in 1905. His "Tables of Functions with Formulae ...
eldo's user avatar
  • 48k
0 votes
1 answer
24 views

ParametricPlot not plotting domain end points

Consider the parametric plot ...
lineage's user avatar
  • 1,114
0 votes
0 answers
27 views

Why can't Mathematica simplify $\left(e^{t/m}(gm)^{1/k}\right)^{-k}$? [duplicate]

It seems Mathematica can't simplify this Simplify[(e^(t/m)*(g*m)^(1/k))^(-k)] The result is I think it should be
Y. zeng's user avatar
  • 445
1 vote
2 answers
60 views

How to find Maximize of $(m^2 + n^2)/(5 - m n)$ where $m$, $n$ and $(m^2 + n^2)/(5 + m n)$ are integer numbers?

I am trying to find Maximize of the expression $(m^2 + n^2)/(5 - m n)$ where $m$, $n$ and $(m^2 + n^2)/(5 - m n)$ are integer numbers. I tried ...
John Paul Peter's user avatar
1 vote
0 answers
47 views

How does Mathematica compile patterns for pattern matching?

I have been trying to understand how Mathematica is able to compute the values it does. The core evaluation process is very well documented and can be found on various question over here, but they ...
Rui Pedro's user avatar
1 vote
1 answer
60 views

Why is the result of "D[y == Log[x*y], x]" "0 == 1/x"? [closed]

In Mathematica 13.3.1, the D[y == Log[x*y], x] gives result 0 == 1/x. It is very weird. At WolframAlpha, its result is ...
Y. zeng's user avatar
  • 445
0 votes
0 answers
11 views

Tensors without explicit specifications in xCoba

In the standard Schwarzschild setup I have the following tensor: ...
mster8390's user avatar
0 votes
0 answers
16 views

How to strip out Graphics exported using `FrontEnd`ExportPacket[..., "InputText"]`?

I've tried converting 913 Mathematica notebooks I've accumulated over the years into text, and the problem I ran into while using this solution is that some files are over 100MBs because they export ...
Yaroslav Bulatov's user avatar
1 vote
2 answers
93 views

Chi-square minimization error

I'm trying to fit some data into a model using the standard procedure of minimizing the chi-square function using this code: ...
Syn1110's user avatar
  • 61
0 votes
0 answers
47 views

Method of lines - Dirichlet and mixed BC

I have a dissolution problem to solve with two equations (everything is in dimensionless form - concentration, time and distance - EDIT: that came from the second Fick's law, where the distance was ...
Larissa Santos's user avatar
0 votes
0 answers
21 views

Can I delete it by specifying the number of the numbered Print Cell?

The following is a simple example. i = 0; Button["Make Cell", Print[Row[{CellNumbered[ ++i]}]]] I want to give the number to the printed cell. And I ...
Hoony's user avatar
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1 vote
0 answers
18 views

Can I limit the mouse prompt position in InputField?

I wrote the Manipulate code in double quotation marks in InputField. Manipulate[str, Style[Control@{str, " "}, 20]] Above, I can create a prompt status ...
Hoony's user avatar
  • 1,470
2 votes
1 answer
88 views

Extending an Animated Vector Flow from Two to Three Dimensions

I found some code for animating a two-dimensional vector flow on stackexchange. Unfortunately, I can't find the original post so I can't credit the author. I have modified the code for my purposes ...
B flat's user avatar
  • 5,463
0 votes
0 answers
38 views

ReplacePart will not accept coordinates [closed]

So, curiously I get an error claiming that entries like {40,80}, {41,80}... will not work as a valid positional input. I'm making these from creating a table. So, I tried manually entering these ...
Skye's user avatar
  • 1
2 votes
1 answer
33 views

Is there a non-allocating way to modify elements of single-reference packed arrays?

I need to repeatedly increment cuboidal chunks of a 3D image. The image is large - on the order of 1G elements. The only way I know of doing it using built-in Image functions is: ...
Kuba hasn't forgotten Monica's user avatar
5 votes
2 answers
186 views

Is it possible in Mathematica to get a step-by-step evaluation of the following?

Is it possible in Mathematica (or WolframAlpha["...]") to get a step-by-step evaluation of the following? ...
1_student's user avatar
  • 605
1 vote
1 answer
89 views

Unable to improve accuracy of MethodOfLines

I'm studying a PDE which roughly models a rope subjected to driving on one end. The coordinate $v$ is related to physical time $t$ via the relation $v=t-x$. I'd like to solve the initial value problem ...
phonon's user avatar
  • 45
4 votes
2 answers
171 views

Nonlinear model fit not working

Probably a very simple fix, but I'm trying to fit a simple exponential. Even when I put in good guesses, the model won't fit the data. Any suggestions? ...
icebox207's user avatar
0 votes
0 answers
63 views

Badly conditioned matrix for boundary ODE

I have a coupled boundary ODE with dependent variables $u=u(x)$ and $z=z(x)$, $$u'' - \frac{1}{z} \left( -3 + u'^2 (3 - c\; e^{-g u} z^4) - 6 u' z' \right) = 0\tag{1}$$ $$z'' + c\; e^{-g u} z^3 (-3 + ...
mathemania's user avatar
1 vote
1 answer
82 views

Converting Wolfram Language Scripts (.wls) into PDFs

I have just discovered the free (as in free beer) Wolfram Engine, coming with a generous licence. After playing with Mathematica for a while, and missing the notebook feature, I would like to generate ...
antonio's user avatar
  • 111
0 votes
1 answer
60 views

How to plot points on a grid given by two vectors? [closed]

I am trying to do a very simple task that is automatic on Matlab for example, but it is not trivial for me in Mathematica: Given two vectors for example: ...
Daniel Vainshtein's user avatar
0 votes
0 answers
28 views

Connection of MariaDB 11.2 to work with Mathematica 13.3.1

I would like to get the proper driver settings in place to permit the mariaDB database to connect to Mathematica via a JDBC driver running on a Windows11 64-bit machine. I've got mariaDB version 11.2 ...
Stuart Poss's user avatar
  • 1,774
0 votes
0 answers
74 views

How is my code going over the recursion limit?

I don't know how my code is exceeding the recursion limit of 1024. ...
SurvivalWish's user avatar
1 vote
1 answer
60 views

More intuitve way to simplify a simple expression involving two exponential factors

Is there a way to ask Mathematica to simplify expressions it generates, like: $e^{-\frac{A t}{v^3}-\frac{v^2}{2 w^2}} \left(-1+e^{\frac{A t}{v^3}}\right)$ into a more readable form by taking out the ...
kotozna's user avatar
  • 317
5 votes
1 answer
111 views

How to solve the equation $(3^m - 3^n)^2 = 2^a + 2^b$ where $m, n, a, b$ be positive integers?

I am trying to solve the equation $(3^m - 3^n)^2 = 2^a + 2^b$ where $m, n, a, b$ be positive integers. I tried ...
John Paul Peter's user avatar
2 votes
0 answers
28 views

Listing most recently modified sections in Notebook?

I'd like to get a clickable list of all "Sections" that have been recently modified in my notebook, grouped by day of modification. "Modified" Section means, some cell under that ...
Yaroslav Bulatov's user avatar
2 votes
1 answer
226 views

Absolute value of a complex number

I want to calculate |xx|^2. Why can't Mathematica just calculate it? What am I supposed to do here? I just want it to actually calculate it, so that there are no imaginary numbers left. Is that so ...
Σ balls's user avatar
0 votes
1 answer
34 views

Searching directory over a network

I have a network drive mapped on my Windows machine. I need to read data from the network that is nested in a few directories below the root. Example is "G:/Data/folder01/data/date_name/values....
jpskin's user avatar
  • 11
2 votes
1 answer
38 views

By what criteria does Mathematica generate the list of group elements in `GroupElements[group]`?

I ask because aside from always giving the identity element first, I have found a "pattern" associated with the list given by GroupElements[group]. This &...
Phillip Dukes's user avatar
0 votes
0 answers
62 views

Solving the integral equation

Why does Wolfram Mathematica just rewrite my code instead of solving the integral equation? SigmaPhiBegin, SigmaPhiEnd are functions depending on Rho, Rho, bEnd, a, Kappa are constants. What needs to ...
Mark's user avatar
  • 1
2 votes
1 answer
45 views

Export Notebook as Text (in 13.3 &14)

What is the best way to export a notebook as readable plaintext - while preserving as much structure as possible? The motivation here is the need to bulk-ingest notebooks and chunk them (for use in ...
user5601's user avatar
  • 3,601
-1 votes
0 answers
27 views

Specify a tensor or a function with a specific form in xCoba [closed]

Suppose, in the Schwarzschild geometry with the standard coordinates, I wanted to specify an electromagnetic tensor F with the (six) components all being functions of r: A(r), B(r), C(r), D(r), G(r), ...
mster8390's user avatar
1 vote
3 answers
104 views

Plotting |z-2| < 1 under w = z/(z-1)

How can I plot the image of |z-2| < 1 under the transformation w = z/(z-1)? The expected result should look something like ...
internet's user avatar
  • 507
1 vote
1 answer
90 views

Mathieu Floquet solution

Mathematica provides the MathieuC[a,q,z] and MathieuS[a,q,z] functions - as well as some other Mathieu-related functions. Maple ...
Brian Cowan's user avatar
7 votes
1 answer
146 views

Can you explain this substitution rule?

This rule behaves as I expect: b . c + a . b . c /. (b . c) -> x (* x + a . x *) I would expect the same result with this: ...
mikado's user avatar
  • 16.2k
8 votes
5 answers
1k views

Why does Mathematica not recognize a convergent series?

In one of my program run on Wolfram Cloud I run the command: Sum[(-1)^(Floor[k/2])/(k+1),{k,0,Infinity}] and got the response ...
drer's user avatar
  • 689
0 votes
1 answer
33 views

What is the fastest way to change Python environment?

We can see all registered Python environments through FindExternalEvaluators["Python"]. But the user interface will use the last registered one. How to ...
Alexey Golyshev's user avatar
3 votes
1 answer
39 views

Alternatives to Export to write long list as a table on a file

I have a large list (approx 50 millions elements). I could Export it as a table like this: ...
mattiav27's user avatar
  • 6,587
0 votes
0 answers
98 views

Plot and mention extremum with corresponding points of extrema

Let sigma1[v] , sigma2[v] and sigma3[v] with Im(sigmar)<0 (r=1,2,3) are the roots of the following cubic (in sigma^2) Eq (1), say: ...
Nantu Sarkar's user avatar
1 vote
0 answers
36 views

How to place Objects in Graphics in front or behind other objects using Inset[] in Mathematica13.3?

I made several 2DGraphics using Mathematica v12.0. To define if an object is placed in front of another or behind, I simply changed the order of the Inset. In this ...
Cptn Bluebear's user avatar
1 vote
0 answers
36 views

How to assume a function is holomorphic?

For example, for a holomorphic function $f(z)=f(x,y)$, it's well know that $\ln |f|$ is harmonic. I want to check it with mathematica with the following code: ...
gaoqiang's user avatar
15 votes
1 answer
610 views

How can we plot Man Ray's "Shakespearean Equation" w == e^(1/z)?

1. Man Ray Man Ray (1890 - 1976) was an American artist who spent most of his career in Paris. He was a significant contributor to the Dada and Surrealist movements. Man Ray produced major works in a ...
eldo's user avatar
  • 48k
0 votes
0 answers
28 views

Create Constraints Iteratively for NMaximize [closed]

new to Mathematica so sorry for the silly question Trying to crete a list of constraints in Mathematica without typing manually as ...
legendary kaya's user avatar
0 votes
0 answers
35 views

The Value is not Updated in the list/table [closed]

I have following data groupedTerms3rdcycle = GroupBy[term3rdcyclelist, Most -> Last]; where term3rdcyclelist is the list. I ...
j.doe's user avatar
  • 123

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