在python中读取日志文件

根据我对您的数据的了解,以下正则表达式应该可以工作:

pattern = "Iteration\s+(\d+)|detection_eval\s+=\s+(.+$)"
for it,de in re.findall(pattern, log, flags=re.M):
    if it: 
        print('Iteration', int(it))
    if de:
        print('detection_eval', float(de))
#Iteration 200
#detection_eval 0.00273318

但是,一次读取整个日志文件通常是个坏主意。考虑一次读一行:

with open(log_file, 'r') as log_file2:
    for line in log_file2:
        for it,de in re.findall(pattern, log):
            if it: 
                print('Iteration', int(it))
            if de:
                print('detection_eval', float(de))

使用 re.search

演示:

import re

with open(log_file, "r") as infile:
    for line in infile:
        iteration = re.search("Iteration (\d+)", line)
        if iteration:
            print iteration.group()

        detection_eval = re.search("detection_eval = (\d.*)", line)
        if detection_eval:
            print detection_eval.group()

输出:

Iteration 200
detection_eval = 0.00273318

或使用 re.findall

iteration = re.findall(r"Iteration (\d+)", log )
detection_eval = re.findall(r"detection_eval = (\d.*)", log )