Printing subscript in python

问题:

In Python 3.3, is there any way to make a part of text in a string subscript when printed?

e.g. H₂ (H and then a subscript 2)

回答1:

If all you care about are digits, you can use the str.maketrans() and str.translate() methods:

>>> SUB = str.maketrans("0123456789", "₀₁₂₃₄₅₆₇₈₉")
>>> SUP = str.maketrans("0123456789", "⁰¹²³⁴⁵⁶⁷⁸⁹")
>>> "H2SO4".translate(SUB)
'H₂SO₄'

Note that this won't work in Python 2 - see Python 2 maketrans() function doesn't work with Unicode for an explanation of why that's the case, and how to work around it.

回答2:

The output performed on the console is simple text. If the terminal supports unicode (most do nowadays) you can use unicode's subscripts. (e.g H₂) Namely the subscripts are in the ranges:

• 0x208N for numbers, +, -, =, (, ) (N goes from 0 to F)
• 0x209N for letters

For example:

In [6]: print(u'H\u2082O\u2082')
H₂O₂

For more complex output you must use a markup language (e.g. HTML) or a typesetting language (e.g. LaTeX).