EulerBot

Discord bot for typesetting LaTeX and Python programming.

Invite Euler bot

LaTeX

• The bot renders messages containg LaTeX code. Any message containing at least a pair of dollar signs $ or \begin will be rendered as a PNG image.

• The bot also supports Markdown syntax within $\LaTeX$ messages.

• The bot can also handle picture or tikzpicture environment.

• LaTeX code is rendered by KaTeX. You can specify KaTeX options with the command !katex gistd id where gistid is the id of a public gist containing a JSON object.

• Example of a Discord message and the generated image.

# Test

- Inline math : $x\mapsto x^2$ induces a bijection from $\mathbb R_+$ onto $\mathbb R_+$.

- tikzpicture image

\usetikzlibrary{quotes,angles}
\begin{tikzpicture}[thick,scale=5, every node/.style={scale=5}]
  \draw
    (3,-1) coordinate (a) node[right] {a}
    -- (0,0) coordinate (b) node[left] {b}
    -- (2,2) coordinate (c) node[above right] {c}
    pic["$\alpha$", draw=orange, <->, angle eccentricity=1.2, angle radius=1cm]
    {angle=a--b--c};
\end{tikzpicture}

- Python code

```python
def f(x):
  return x**2
```

- Displaystyle math
$$
\int_{-\infty}^{+\infty}e^{-t^2}\mathrm{dt}=\sqrt\pi
$$

• Example of a katex gist

{
  "macros": {
    "\\cC": "\\mathcal{C}",
    "\\cD": "\\mathcal{D}",
    "\\cP": "\\mathcal{P}",
    "\\la": "\\lambda",
    "\\va": "\\varphi",
    "\\dF": "\\mathbb{F}",
    "\\dK": "\\mathbb{K}",
    "\\dN": "\\mathbb{N}",
    "\\dQ": "\\mathbb{Q}",
    "\\dR": "\\mathbb{R}",
    "\\dC": "\\mathbb{C}",
    "\\dU": "\\mathbb{U}",
    "\\dZ": "\\mathbb{Z}",
    "\\lb": "\\left[\\!\\left[",
    "\\rb": "\\right]\\!\\right]",
    "\\card": "\\operatorname{card}",
    "\\vect": "\\operatorname{vect}",
    "\\dim": "\\operatorname{dim}",
    "\\deg": "\\operatorname{deg}",
    "\\ident": "\\operatorname{Id}",
    "\\stab": "\\operatorname{Stab}",
    "\\Im": "\\operatorname{Im}",
    "\\Ker": "\\operatorname{Ker}",
    "\\conj": "\\overline",
    "\\te": "\\theta",
    "\\eps": "\\epsilon",
    "\\si": "\\sigma",
    "\\al": "\\alpha"
  }
}

• The bot's message is updated/deleted whenever the author's message is updated/deleted.

Python

• Use the !python command to interpret Python code.

• Example of a Python message and generated output

!python
def doubles(l):
  return [2*x for x in l]
print(doubles(range(10)))

---

Code

def doubles(l):
  return [2*x for x in l]
print(doubles(range(10)))

Sortie

[0, 2, 4, 6, 8, 10, 12, 14, 16, 18]

• You can use the numpy package.

• You can also the matplotlib package. Each call to show() will generate an image.

• Example of a message using numpy and matplotliband the generated output.

!python
import numpy as np
import matplotlib.pyplot as plt
X=np.linspace(0,1,100)
Y=np.exp(X)
plt.plot(X,Y)
plt.show()

---

Code

import numpy as np
import matplotlib.pyplot as plt
X=np.linspace(0,1,100)
Y=np.exp(X)
plt.plot(X,Y)
plt.show()

Sortie

python