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pythonregexpython-re

Regex Match two specific characters and get first numbers followed by those Characters

If user inputs VX is 20 m/s VY is 40 m/s VZ is 60 m/s.

Expected results are the Axis VX and 20 from the input.

The code below also recognizes the other numbers 40 & 60 also.

(VX)|(vx)|(Vx)|(vX)|[0-9]
Solution

  • Use

    (?P<axis>vx)\s+\w+\s+(?P<value>\d+)

    Add re.IGNORECASE. See regex proof.

    EXPLANATION

     - Named Capture Group axis (?P<axis>vx)
   - vx matches the characters vx literally (case insensitive)
 - \s+ matches any whitespace characters between one and unlimited times, as many times as possible, giving back as needed (greedy)
 - \w+ matches any word characters between one and unlimited times, as many times as possible, giving back as needed (greedy)
 - \s+ matches any whitespace characters between one and unlimited times, as many times as possible, giving back as needed (greedy)
 - Named Capture Group value (?P<value>\d+)
   - \d+ matches a digits between one and unlimited times, as many times as possible, giving back as needed (greedy)

    Python code demo:

    import re
text = r'VX is 20 m/s VY is 40 m/s  VZ is 60 m/s'
p = re.compile(r'(?P<axis>vx)\s+\w+\s+(?P<value>\d+)', re.IGNORECASE)
match = p.search(text)
if match:
    print(match.groupdict())

    Results: {'axis': 'VX', 'value': '20'}