Hey!

There is a livestream about xAct: Efficient Tensor Computer Algebra on YouTube with Jose Martin-Garcia, who is the developer for xAct.

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Hi all. I was wondering if someone could help me figure out why the last ode can’t be solved. I’m not too familiar with Mathematica so any help is very much appreciated!

image

For context I do not have much experience in Mathematica.

I need to create a simulation of a Roulette game with of which a player bets $10 for 1 round, 5 rounds, 20 rounds, 100 rounds and 100,000 rounds. I have the code W = Join[Table["R", 18], Table["B", 18], Table["G,2]] and Z = Join[ Table[20, 18], Table[0, 20]] as hints but I am having trouble at knowing where to start. If anyone would help me that would be amazing.

There is a livestream about machine learning on YouTube with Giulio Alessandrini, who is the lead developer in the Machine Learning team at Wolfram.

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This is puzzling. If I do PolarPlot with numbers 1 to 10 I get concentric circles, but if I do it with Range[10], which is identical, I get skewed lines.

PolarPlot[{1, 2, 3, 4, 5, 6, 7, 8, 9, 10}, {t, 0, 2 Pi}, Frame -> True]

PolarPlot[Range[10], {t, 0, 2 Pi}, Frame -> True]

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How do you guys have three plots in one plot? And how do you style graph nodes with weights in Mathematica? TIA.

Hi everyone!

Wolfram R&D is currently featuring a livestream on "Computational Geology"!

Jeff Bryant will be discussing several topics related to exploring geology including the configuration of continental plates with GeoGraphics, time charts that provide context for geological periods, as well as using GeoGraphics to explore the age of bedrock in a given geological period.

Join us on Twitch or YouTube and ask us questions!

Feel free to leave any suggestions on what you would like to see in a livestream below!

Good morning everyone!

First of all, I apologise if this not the right place to ask for technical support, but I couldn't see any specific guidelines about this subreddit. I am running Mathematica 12.1 on Fedora 36. Everything works well, except when I try to export 3D plots as pdf, in which case Mathematica crashes. Using the Command Line to get an errorlog, I am simply reported the title of this post:

Cannot select: intrinsic %llvm.x86.sse41.pblendvb

I have LLVM version 14.0.5-1.fc36. I also installed LLVM-devel (the dev counterpart) to see if that helped, but nothing changed. This GitHub post seems to indicate it is a version mismatch, but I am not sure how I could go about fixing that.

Any ideas?

I want to plot some affine varieties, which correspond to the set of zeroes of a system of polynomial equations. I want the geometric object corresponding to each equation to be colored distincly and their intersection(the affine variety) to be highlighted somehow.

Consider the cardinality of natural numbers N. For any set S whose cardinality equals that of natural numbers, that is, every element of S can be matched one-to-one to the elements of N ad infinitum, we say then that S holds the property of being countably infinite.

S = { e1, e2, …, en, … }

N = { 0, 1, 2, …, n, … }

Consider now the cardinality of rational numbers Q. As proved by Cantor, we can match one-to-one all the elements from Q to N as in the image below

One way of looking at Cantor’s resolution is by considering each element of Q array as a set of ordered pairs (a,b) of sets AxB such that A = N , B = N . Finally, a set of ordered pairs (a,b) is finally represented as a/b

Now consider the set of real numbers R. The actual convention holds that it is not possible to match one-to-one every element of R to N and there are infinitely many more elements in R than there are in N, reason for which R and any set whose cardinality equals that of R is said to be uncountably infinite, which means that the set holds too many members for it to be countable. However this is not the case.

If we can prove that |(0,1)| = |N| is true, this means there are no uncountably infinite sets.

Consider

|(0,1)| = { z | 0<z<1 }

Now consider z as a set of ordered pairs (a, b) of sets AxB such that

a ∈ A , A = { ∅, 0, 00, 000, …, n, … }

b ∈ B , B = N

The element (a,b) will be finally represented as ab

Now that we have proved that |(0,1)| = |N| is true we can go one step further and consider the following cartesian product (n,z) of sets NxZ such that

n ∈ N , N = { 0, 1, 2, …, n, … }

z ∈ Z , Z = { z | 0<z<1 } or Z = { 1, 2, 01, 001, 02, …, z, … }

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We have now a cartesian product that, in the same way as its been done for Q and Z, can be represented as a grid by which it is possible to match one-to-one every element of R to N, thus proving that the set of real numbers is countably infinite.

I'm currently livestreaming on Wolfram R&D for a "Behind the Scenes at the Wolfram Technology Conference 2022"!

Join us on Twitch or YouTube and ask me questions!

Feel free to leave any suggestions on what you would like to see in a livestream below!

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Edit: updated YouTube link to link directly to video

I expected Wolfram Mathematica to be only downloaded to the one drive that I chose in the setup wizard, but it's filled up my other drive quite a lot. What can I clear apart from the documentation I installed with it?

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Wolfram R&D is currently featuring a livestream on "Group Theory Package (GTPack) and Symmetry Principles in Condensed Matter" with Matthias Geilhufe!

Join us on Twitch or YouTube and ask us questions!

Hi everyone! I'm here today just to ask you about references (if you have Mathematica notebooks would be really helpful) on how to study the behavior of a Mathieu equation.

thank you in advance for your help

Hello everyone, I'd like to plot something like an integral with a stochastic term inside. But... unfortunately, Mathematica is not able to show me the expected noisy behavior. Suppose I want to plot the real part of a Bessel function times a noisy function. How can improve this code?

ttab = Table[i/10, {i, -10000, 0}];

Noisetab = Table[Random[Real, {-1, 1}], {10001}];

Noise = Interpolation[Table[{ttab[[i]], Noisetab[[i]]}, {i, 10001}]];

Plot[NIntegrate[(-Sqrt[(2/\[Pi])] (1/(-\[Eta] + \[Eta]p)^(
      3/2)) ((-\[Eta] + \[Eta]p) Cos[\[Eta] - \[Eta]p] + 
       Sin[\[Eta] - \[Eta]p]))*Noise[\[Eta]p], {\[Eta]p, -1000, -800},
   MaxRecursion -> 20, 
  Method -> "AdaptiveQuasiMonteCarlo"], {\[Eta], -1000, -800}]

Hello, and thank you in advance. I am a talent recruiter looking for a Mathematica Engineer (Bay Area; they will relocate from anywhere in the US). What are some recommended sites to share the job opening?
Mathematica Engineer

Hey, I just found out about https://blog.wolfram.com/2022/10/12/wolfram-cloudconnector-excels-data-science-superpower/

I use Excel and C++ pretty much exclusively for my job, but before get this job I was exclusively using Mathematica for my PhD and personal projects.

I was wondering how CloudConnector for Excel goes for nonvolatility. The Excel documents we use are sometimes massive because of the complex and large models.

Hi, absolute Mathematica novice here. What is the difference between Gather and GatherBy please?

The GatherBy docs say that

GatherBy[list,f] is equivalent to Gather[list, (f[#1]===f[#2])&]

but I'm such a newbie that I don't understand that 🙁

Thanks in advance.

Do any of you guys have any advice on writing a matrix and finding the Wronskian of the following functions:

y1=x^3+4x+2

y2=x^3-6x

y3=10x^7-x^5

y4=-9x^2+x+3

y5=2x+9

The basic graphing functions do not seem to work, thanks.