捕获科学记数法并转换为字符串

Question

I need to capture occurrences of scientific notation in a string and convert the notation in string format using python.

eg E-100 and/or e-100 should be represented as 1E-100 in string format.

So far I have following code

>>> import re
>>> num = "My numbers are E-100 and e-100"
>>> print(num)

My numbers are E-100 and e-100

>>> re.findall('[eE]?[+-]?\d+(?:\.\d+)?(?:[eE][+-]?\d+)?', num)

['E-100', 'e-100']

This prints numbers as a list.

How can I convert each of this number to 1E-100 and print in string format.

Update: This should work with all numbers eg 2e-123 should be represented in string format as 2E-123

Thanks in advance !!

Answer 1

You can use replace operation.

Code:

import re
num = "My numbers are E-100, e-100, e+07, E-234, 2e-09 "
arr = re.findall('[eE]?[+-]?\d+(?:\.\d+)?(?:[eE][+-]?\d+)?', num)

for i in range(len(arr)):
    arr[i] = arr[i].replace('e', 'E')
    if arr[i][0] == 'E':
        arr[i] = arr[i].replace('E', '1E')

print(arr)

Output:

['1E-100', '1E-100', '1E+07', '1E-234', '2E-09']