文本文件从txt文件读取输入变量

时间:2020-03-02 18:57:31

标签: python python-3.x file

我确实有这种格式的文本文件

instance_name = "small_instance_01_simple";
d = 2; 
r = 3;
SCj = [80 57]; 
Dk = [96 22 14];
Cjk = [[81 51 31]  [82 47 54]];

如何在python代码中获取这些变量的值?我尝试了更多方法,但未成功

1 个答案:

答案 0 :(得分:3)

首先让我们导入re并定义类似文件的对象:

import re

s = StringIO("""
    instance_name = "small_instance_01_simple";

    d = 2;

    r = 3;

    SCj = [80 57];

    Dk = [96 22 14];

    Cjk = [[81 51 31] [82 47 54]];
""")

parse_value函数尝试将expr解析为基元,如果它无法作为序列并最终作为字符串失败:

def parse_value(expr):
  try:
    return eval(expr)
  except:
    return eval(re.sub("\s+", ",", expr))
  else:
    return expr

parse_line函数解析每一行并返回可变名称和值(如果有):

def parse_line(line):
    eq = line.find('=')
    if eq == -1: raise Exception()
    key = line[:eq].strip()
    value = line[eq+1:-2].strip()
    return key, parse_value(value)

现在让我们提取变量:

vars = {}
for line in s.readlines():
  try:
    key, val = parse_line(line)
    vars[key] = val
  except:
      pass

让我们检查一下我们拥有什么:

for key, value in vars.items():
  print(key, value, type(value))

输出:

instance_name small_instance_01_simple <class 'str'>
d 2 <class 'int'>
r 3 <class 'int'>
SCj [80, 57] <class 'list'>
Dk [96, 22, 14] <class 'list'>
Cjk [[81, 51, 31], [82, 47, 54]] <class 'list'>