Function 将输入表达式拆分为令牌单元（python）

Question

def get_token_list(expr):
    token_list_initial = expr.split(' ')
    token_list=[]
    for token in token_list_initial:
       if token in '+-/*^()':
          token_list.append(token)
       elif token == ' ':
          continue
       elif token in '0123456789':
          token=float(token)
          token=str(token)
          token_list.append(token)
    return token_list

There may be a space between the operator and the operand. Both operators and operands must be returned as strings in a list. Operand must be float.

Eg.

input: 1+2 *3/(4+5)

output: ['1.00', '+', '2.00', '*'......]

I am not sure what is wrong. I would really appreciate it if you taught me.

Answer 1

I tried to do it using regex, take a look:

import re

input = "1+2 *3  (4+5)"
input = input.replace(' ','')

print([i for i in re.split('([^0-9])',input) if i != ''])

Hope it helps!