mirror of
https://github.com/Keychron/qmk_firmware.git
synced 2024-11-30 12:47:37 +06:00
751316c344
You can now use `qmk info` to get information about keyboards and keymaps. Co-authored-by: Erovia <Erovia@users.noreply.github.com>
34 lines
973 B
Python
34 lines
973 B
Python
"""Parse arbitrary math equations in a safe way.
|
|
|
|
Gratefully copied from https://stackoverflow.com/a/9558001
|
|
"""
|
|
import ast
|
|
import operator as op
|
|
|
|
# supported operators
|
|
operators = {ast.Add: op.add, ast.Sub: op.sub, ast.Mult: op.mul, ast.Div: op.truediv, ast.Pow: op.pow, ast.BitXor: op.xor, ast.USub: op.neg}
|
|
|
|
|
|
def compute(expr):
|
|
"""Parse a mathematical expression and return the answer.
|
|
|
|
>>> compute('2^6')
|
|
4
|
|
>>> compute('2**6')
|
|
64
|
|
>>> compute('1 + 2*3**(4^5) / (6 + -7)')
|
|
-5.0
|
|
"""
|
|
return _eval(ast.parse(expr, mode='eval').body)
|
|
|
|
|
|
def _eval(node):
|
|
if isinstance(node, ast.Num): # <number>
|
|
return node.n
|
|
elif isinstance(node, ast.BinOp): # <left> <operator> <right>
|
|
return operators[type(node.op)](_eval(node.left), _eval(node.right))
|
|
elif isinstance(node, ast.UnaryOp): # <operator> <operand> e.g., -1
|
|
return operators[type(node.op)](_eval(node.operand))
|
|
else:
|
|
raise TypeError(node)
|