如何分配给python3中数学运行的EXEC输出的字典

Question

我创建了以下功能：（缩进可能不是示例中的完美）

def TestFunction():
    profile_info_per_sec = {}
    profile_info_per_sec['DB CPU(s):'] = 1
(snipped)
    l, g = locals().copy(), globals().copy()
    print ('------- 1.0 Just Printing the Value -------')
    varprint = 'print(' + 'float(' + str(finalvar) + '))'
    print ('1.0 To Be Executed: ', varprint)
    exec (varprint)
    print (locals() == l, globals() == g)
    print ('*******')
    print ('------- 2.0 Just Printing the Value -------')
    varprint = 'x=' + 'float(' + str(finalvar) + ')nprint(x)'
    print ('2.0 To Be Executed: ', varprint)
    exec (varprint)
    print (locals() == l, globals() == g)
    print ('*******')
    print ('------- 2.1 Just Printing the Value -------')
    varprint = 'a=5nb=7nsum=a+b'
    print ('2.1 To Be Executed: ', varprint)
    varprint_res = {}
    exec (varprint,{},varprint_res)
    print (varprint_res)
    print (locals() == l, globals() == g)
    print ('*******')

这正在起作用，生成以下输出：

------- 1.0 Just Printing the Value -------
1.0 To Be Executed:  print(float(profile_info_per_sec['DB CPU(s):']))
1.0
False True
*******
------- 2.0 Just Printing the Value -------
2.0 To Be Executed:  x=float(profile_info_per_sec['DB CPU(s):'])
print(x)
1.0
False True
*******
------- 2.1 Just Printing the Value -------
2.1 To Be Executed:  a=5
b=7
sum=a+b
{'a': 5, 'b': 7, 'sum': 12}
False True
*******

但是，当我尝试添加以下代码时，这已经不再起作用了。

 print ('------- 3.0 Capturing Value -------')
 varprint = 'x=' + 'float(' + str(finalvar) + ')nx=x+x'
 varprint_res = {}
 print ('3.0 To Be Executed: ', varprint)
 exec (varprint,{},varprint_res)

输出错误是：

------- 3.0 Capturing Value -------
3.0 To Be Executed:  x=float(profile_info_per_sec['DB CPU(s):'])
x=x+x
Traceback (most recent call last):
  File "XmlTestCase.py", line 111, in <module>
    TestFunction()
  File "XmlTestCase.py", line 70, in TestFunction
    exec (varprint,{},varprint_res)
  File "<string>", line 1, in <module>
NameError: name 'profile_info_per_sec' is not defined

所以，我知道我应该在字典中获取此输出，但是，代码中动态执行的内容也是字典，我相信问题与之相关。

P.S：一些背景信息是变量和数学操作来自XML文件，需要处理，结果应保留在Python脚本中以进行进一步处理。

你们能为此提供帮助吗？

预先感谢。

问：

eri

Answer 1

exec()的第三个参数是一个词典，用于查找局部变量，而不是函数的正常局部变量。因此，您需要向其添加profile_info_per_sec，以便exec()可以找到该变量。

varprint_res = { 'profile_info_per_sec': profile_info_per_sec }