I am looking for a way to place a bold dot above letters/variables to signify the time derivative. Ideally for both Python itself, but mainly for matplotlib axes.
I would expect something similar like:
print(u'1\u0305')
Although this is a very basic question, I cannot find anything, especially, because the term "dot notation" in Python is something completely different.
Thank you in advance.
The value (unicode code point) for a dot above letters (combining dot above) is '\u0307', so combining it with any letter will give you that letter but with a dot above.
dot = '\u0307'
print('n' + dot) # ṅ
print('a' + dot) # ȧ
print('v' + dot) # v̇
An arrow right above is often used if you want these to refer to a vector.
arrow = '\u20D7'
print('n' + arrow) # n⃗
print('a' + arrow) # a⃗
print('v' + arrow) # v⃗
Alternatively, you could use a combining macron.
macron = '\u0304'
print('n' + macron) # n̄
print('a' + macron) # ā
print('v' + macron) # v̄
Use LaTeX notation with matplotlib.
import numpy as np
from matplotlib import pyplot as plt
plt.plot(np.random.random((5,)))
plt.xlabel('x')
plt.ylabel(r'$\dot{y}$')
You can name your variables using unicode characters like Ted showed, but in my opinion that just makes programming more difficult because standard keyboards don't have a way to type those characters easily.