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How to set the precision for the entire notebook

I want to do various computations conditional on a given precision for the entire notebook. I use the following code: ...
Tugrul Temel's user avatar
  • 5,480
1 vote
0 answers
34 views

functional derivative with respect to the partial derivative of the metric with xAct

I want to compute the functional derivative with respect to a partial derivative of the metric with the mathematica package xAct. This is what I have tried so far: ...
Carmen López Jurado's user avatar
2 votes
1 answer
74 views

Rotating text in the Epilog of a plot results in distortion

I want to rotate text in a plot. When I rotate by 90 degrees, or 180, it's perfectly OK. But if I want to rotate to 60 or 45 degrees, then the text appears distorted (see example below). How can I fix ...
lia's user avatar
  • 145
3 votes
1 answer
79 views

Nice output for FourierTransform

I want to demonstrate FourierTransform in a lecture. However if you give FourierTransform a differential equation it does not ...
Hugh's user avatar
  • 16.1k
3 votes
4 answers
204 views

Different answers when attempting replacement of function argument

I have three function computing Fibonacci numbers which return correct answers when directly called with e.g. fib1[10]: ...
youyou's user avatar
  • 123
1 vote
0 answers
31 views

Monitor inside core function

I like DistanceMatrix: its performance is surprisingly high, even for a big data. However, for a huge arrays and custom ...
lesobrod's user avatar
  • 1,197
3 votes
1 answer
120 views

Why does using a sparse matrix for least squares instead slow down the speed?

Here is the code. The matrix appears to be relatively sparse in terms of its visual representation, but why does using least squares result in significantly slower speed compared to the previously ...
Yilin Cheng's user avatar
0 votes
0 answers
22 views

Simplify vector calculus based on component splitting

I am interested in verifying a few Vector Calculus expressions using Mathematica. These expressions are based on splitting a vector field into its transverse components (in the xy- plane) and ...
orlandini's user avatar
9 votes
5 answers
3k views

Digits of Pi in colored spiral

In How to make the digits of π go around in a spiral like this? it is described how to plot pi in a spiralform (in my case as binary number): ...
ralf_7's user avatar
  • 93
0 votes
0 answers
30 views

Function asymptotics showing different result after inter integration [closed]

I have a function fg[r_, t_, t2_, \[Phi]_, DR_]. I want to do the following Integrate it for t2 from 0 to t Then take the asymptotic limit r-> 0 The result of ...
AB1998's user avatar
  • 1
0 votes
1 answer
73 views

Which condition is better for WhenEvent?

I'm solving a non-linear system with NDSolve. See my previous post In the WhenEvent, which one is better for ODE solving ...
metroidman's user avatar
2 votes
1 answer
89 views

MaTeX text looks shabby when latex generated pdf is not zoomed

I want to use Matex for the figures in my plots which I eventually would like to use in overleaf. I create a plot and use Matex in it and right click on it to save as pdf. I then use this pdf in ...
Razor's user avatar
  • 155
9 votes
0 answers
95 views

Searching AnatomyData efficiently

I really like AnatomyPlot3D, but find it exceedingly difficult to find Mathematica's terminology for an anatomical structure. Listing all of them and searching by ...
David G. Stork's user avatar
2 votes
3 answers
370 views

How to handle units of measurement?

I'm trying to understand how Mathematica handles units of measurement. That is I expect that a calculation should return a certain unit, but I don't succeed. Let's consider this example: ...
Teodoro Marinucci's user avatar
0 votes
0 answers
64 views

Maximizing a function that is only defined numerically

I have a function of multiple variables that is only defined numerically. I am trying to maximize the function and find the critical points as fucntions of two parameters p and s using FindRoot but I ...
jcl's user avatar
  • 1
7 votes
3 answers
122 views

Speed up this computation involving NSolve many times?

Can you think of a way of speeding up this computation ? I don't. ...
anderstood's user avatar
  • 14.2k
0 votes
0 answers
33 views

Trouble implementing switching hybrid system with NDSolve

I'm trying to use NDSolve to simulate a hybrid nonlinear system that switches between different linear behaviors based on states and inputs (i.e. switching from one linear behavior to another) which ...
Cameron Alred's user avatar
0 votes
0 answers
396 views
+50

How to include impulses in differential equations?

I have two coupled differential equations as follows: $$S'(t) = - \frac{a}{1 + B(t)} S(t),$$ $$B'(t) = \frac{c}{1 + S(t)} B(t) (1 - B(t)) - d B^2(t) \Big( \frac{1 - B(t)}{B(t)} \Big)^n,$$ where $a$, $...
Tim's user avatar
  • 41
0 votes
0 answers
37 views

Euler angles and WignerD, a question of signs

Express a 3D point as a linear combination of Spherical Harmonics, then rotate that point to a new position and find the new expansion in SH : ...
Wouter's user avatar
  • 1,333
0 votes
0 answers
39 views

How to pattern match multivariate integral?

I have been using a pattern Integrate[c_ f_, it:{x_Symbol, __}] :> c Integrate[f, it] /; FreeQ[c, x] which matches an integral and pulls out c if c has no ...
Luca's user avatar
  • 83
2 votes
0 answers
39 views

Extracting tables from .pdf

Can we construct some automated method for extracting tables from pdfs? I can get decently far by just copy and pasting its content and splitting at newlines but it would be great if it was possible ...
Kvothe's user avatar
  • 4,197
0 votes
2 answers
91 views

How to build the following region?

Consider a 3D figure defined by the dependence $\Delta x(z),\Delta y(z)$. One example is a pyramidal frustum, for which $\Delta x, \Delta y$ are linear functions of $z$, and $z$ lies inside the ...
John Taylor's user avatar
  • 4,642
7 votes
2 answers
351 views

Why does Blank sometimes not match the empty expression?

Consider these examples: ...
user7427029's user avatar
0 votes
1 answer
50 views

Plotting an integral with solving for a specific constant [closed]

Given an Integral I(t) which is a function of a constant tc, this constant is determined with the condition I(tc)=0, how can I add this condition?
Med Ch's user avatar
  • 117
0 votes
1 answer
47 views

Pointwise convergence of Fourier series: partial sum animation not rendering plot

I'm new to Mathematica (13.3) and I'm attempting to demonstrate the pointwise convergence of the Fourier series for the square wave function f in particular, by showing via Animate/Manipulate that as ...
Pascal Tchakouté's user avatar
5 votes
1 answer
147 views

Why is the graph size decreasing in 'Column'?

I printed out the graph in two ways. Plot[Sin[x], {x, -3, 3}] Column[{ "Plot[Sin[x],{x,-3,3}]", Plot[Sin[x], {x, -3, 3}] }] Comparing the results of the ...
Hoony's user avatar
  • 1,480
0 votes
1 answer
51 views

Numerical Integration without giving all values [closed]

Is there a way to solve expressions numerically, while keeping other variables. For example, I want to Integrate the expression below for $\theta p,\theta q$ while keeping other things as it is. The ...
Lelouch's user avatar
0 votes
0 answers
100 views

Mathematica program reopen problem [closed]

Has anyone encountered such a problem, every time after completing an MMA program, running and exiting it, then opening it again, it becomes like this below: And not just this program, all will become ...
Xu Wang's user avatar
4 votes
3 answers
629 views

How to remove a high accuracy numerical number from a list?

My numerical calculation gives a list of numbers list = {-0.36, 0.2499999999999992, -0.21, 0.36, 0.36}, I want to delete 0.25 ...
MMA13's user avatar
  • 4,265
0 votes
1 answer
70 views

PiecewiseExpand fails to address assumptions

PiecewiseExpand seems to ignore more complex assumptions. Here's an example: ...
user46831's user avatar
  • 633
0 votes
1 answer
67 views

Solving a differential equations with initial condition (piecewise function)

My code: ...
eraldcoil's user avatar
  • 183
1 vote
1 answer
45 views

Error in using the function NDSolve

I am trying to numerically solve a system of ordinary differential equations. ...
Viktoriya Kukanova's user avatar
1 vote
2 answers
97 views

How to construct a custom-made matrix conditional on a set of rules?

The following code does what I intend to achieve; however, it is too cluttered for a simple matrix operation. I like to reduce the code to a one-line code as a ...
Tugrul Temel's user avatar
  • 5,480
0 votes
0 answers
99 views

Apply the IntegrateChangeVariables function correctly

Please help me apply the IntegrateChangeVariables function correctly for my case. I need to change the integration variable from Tau to b(t). * in the photo corresponds to Begin in WM. Photo 3 shows ...
Mark's user avatar
  • 1
2 votes
1 answer
48 views

How to linearize these terms in many different variables? [duplicate]

How to linearize these terms in q[t] and p[t,y] ...
Dr. phy's user avatar
  • 213
3 votes
2 answers
125 views

Choosing desired text on the axis

I've got this plot for instance. Plot[x, {x, 0, 5}, Frame -> True] how can I insert a text on the axis, for exapmple between 1 and 2 I want to write "a&...
lia's user avatar
  • 145
0 votes
0 answers
54 views

Seeking Wolfram Mathematica Techniques for Detailed Step-by-Step Solution of Integral Equation Transformation [closed]

Hello Mathematica Community, I am working on a mathematical problem where I need to transform an integral equation into a simpler form using Euler's Formula and the Error Function. My current ...
Rob_'s user avatar
  • 1
0 votes
1 answer
85 views

How to make the function compile into C faster, and how to determine which portion of the code occupies more memory?

If changing the value of 'n' from 2 to 3 in the above code increases the compilation time from one minute to ten minutes, is there a way to speed it up? Also, the code consumes too much memory during ...
Yilin Cheng's user avatar
0 votes
0 answers
67 views

Method to make this complicated integration from interpolating function? [closed]

Hello I want to do this integral Mu[Psi_, R_] = Integrate[ D[Integrate[Rp f[Psip, Rp]/Sqrt[R^2 - Rp^2], {Rp, 0, R}], R]/ Sqrt[Psi - Psip], {Psip, Psi0, Psi}] ...
Rémy Galli's user avatar
3 votes
2 answers
181 views

Area of ​a parametrically defined function

I can’t solve the problem; I need to find the area of ​​a parametrically defined function. According to the graph, part of the area has a negative sign. ...
Vladimir's user avatar
1 vote
1 answer
64 views

Strange behavior of GroebnerBasis

Recently I tried to solve a multivariate quadratic equation over the reals, but with a parameter value. Since that took too long, I decided to try GroebnerBasis, ...
AYun's user avatar
  • 113
2 votes
0 answers
33 views

Option management with helper functions

I found this example in the documentation of OptionValue Why does f need to be an argument of ...
Crack-Hu's user avatar
7 votes
3 answers
323 views

Sum of its parts - replicating a porcelain sculpture of Nuala O’Donovan

1. Introduction Nuala O’Donovan is an Irish Artist, living and working in Cork. According to her website her research areas are "Irregularities in Patterns in Nature" and "The Geometry ...
eldo's user avatar
  • 48.3k
0 votes
0 answers
33 views

PlotLegends not respecting PlotRange in ArrayPlot and MatrixPlot

I have a matrix that I want to plot. This matrix has data with values ranging from 1400 to -50. If I do ...
CherryBBQ's user avatar
4 votes
1 answer
98 views

How can I find some first terms of a sequence?

I have a sequence knowing that $a_1=15$, $a_{n+1} = a_n + \sqrt{2a_{n+1}-a_n}$. I want to find some the first terms. I tried by my hand ...
Thuy Nguyen's user avatar
4 votes
3 answers
171 views

Automatically extract a factor from a sum of terms and rewrite the sum

I would like to automatically extract the same factor of each term, and thus write a sum such as: $$\frac{4 \sin (2 \pi x)}{\pi }+\frac{4 \sin (6 \pi x)}{3 \pi }+\frac{4 \sin (10 \pi x)}{5 \pi }+...
David G. Stork's user avatar
0 votes
0 answers
57 views

FunctionCompile get IR source code [closed]

A new fancy option to compile WL's function using LLVM is amazing. Is there any way to get the IR's (intermediate representation) representation of it? According to specification there are two forms ...
Kirill Vasin's user avatar
  • 1,175
0 votes
0 answers
62 views

Calculation hangs when called an own function from own loaded package. Debug output shows strange things

I created a package a long time ago and it was working, but in the versions 13.2 13.3 an old created function hangs when called. If I evaluate the same function from a cell manually and then call, it ...
Stiv Zhops's user avatar
0 votes
1 answer
60 views

ArcLength Function Outputting an Integral and Not a Value [closed]

...
Luke Hand's user avatar
0 votes
0 answers
28 views

Kramers-Kronig Relation to find the real and imaginary value of refrective index from absorption data? [closed]

Can anyone please let me know how to use and write a code for Kramers-Kronig Relation to find out the real and imaginary part of reflective index. I have the absorption data of MoS2 in the wavelength ...
Yash Joshi's user avatar

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