I was wondering as a Student in math class is it possible to render functions in form of math plots. An example app that does stuff like that are:
Sadly I cant put links in 
I would love simple syntax like the existing mermaid support:
a{f(x) = x^2+3}
b{f(x) = x^2+2}
c{$$A_{m,n} =
\begin{pmatrix}
1 \\
2 \\
3
\end{pmatrix} + \begin{pmatrix}
1 \\
2 \\
3
\end{pmatrix}
$$}
Some reference Picture if you dont want to use the links:
The App I used in the screenshot is wolframalpha, I cant include links yet.
Joplin is exactly support the mermaid syntax. You can take a look Markdown Guide | Joplin
Is that what you need?
IMO the requested functionality is comparable to this presentation of WolframAplha.
MerMaid syntax does not offer math rendering.
PF/TiK is a " A Portable Graphic Format for TeX". Is it possible to display rendered TeX in a Joplin note?
How do you plot with KaTeX? For example f(x) = x^2+3?
You can't, KaTeX is just for typesetting which is why I was wondering if PGF/TikZ could be used per my previous post.
I tried something like this:
\documentclass {standalone}
\usepackage {pgfplots}
\pgfplotsset {compat = newest}
\begin {document}
\begin {tikzpicture}
\begin {axis}[]
% here comes the code
\end {axis}
\end {tikzpicture}
\end {document}
But it didnt work for me. Thats why I was asking for a feature like math / graph ploting
Is that what you meant with Tikz?
So far as I know, Joplin does not currently support calculations and graphing from formulae.
There are other plugins that are supported which can display graphics based on text input like Mermaid etc. so I was simply wondering if such a plugin could feasibly be developed using something like PGF/Tikz.
KaTeX is a JavaScript library for TeX math rendering on the web which I would read as render TeX math formulas without TeX.
If this works with PGF/TiK then it should be possible to insert for example this:
\tikz \draw[thick,rounded corners=8pt]
(0,0) -- (0,2) -- (1,3.25) -- (2,2) -- (2,0) -- (0,2) -- (2,2) -- (0,0) -- (2,0);
to achieve
which requires access to the TeX extension – I am unsure, if I can do this with a JavaScript.
Besides that, this code is far away from a math formula. Possibly it would be much easier to create a plugin for something like this.
Like 2 dimensional graph ich can greate with Wolframaplha and paste it as a picture. I would be easier or better to use if its was joplin supported. But 3 dimensional graph are a problem for me atm. Thats why I hoped I overlocked a KaTex feature or a mermaid feature. Especially if you want to start doing stuff with vector geometrie I would be kinda nice to have a visualition to show other people.
This seems like a nice start, but it wouldnt solve the issue of rendering 3D-math-plots 
You asked it if supported TeX, I simply replied saying that it supports KaTeX - i.e. it has the capability to one degree or another to display a rendered output from text - i.e. that additional libraries etc. could be developed as plugins to perform other tasks.
The exact knowledge of how it is integrated or how to develop it is far beyond me which is why I asked the question:
THIS was my question.
Maybe this was misleading, but as I described further down, I expect KaTeX as render TeX math formulas without TeX, what very likely excludes PGF/TikZ.
As a solution for the originally asked question (»is it possible to render functions in form of math plots«) I pointed to “Function plot”, which is a JavaScript solution for function plotting.
As KaTeX shows, implementing of existing JavaScript solutions as a plugin is possible. As the attempt of turtle331 shows, \usepackage {pgfplots} obviously has no effect (as I expected).
I don't think any of the current plugins support this. But is there any JS lib that takes a math function as input and renders a graph? If so that could probably be used to create a new plugin.
I found out that math.js supports some sort of plotter but I think its more html than js. I am currently trying to implement it to Joplin. Not sure though if it works.
