Extracting multiple strings using Pythons's regular expression

Question

I have a log file having the following output and I have shortened it as it goes to thousands of lines:

Time = 1

smoothSolver:  Solving for Ux, Initial residual         


        

Answer 1

Your code is writing over iteration_time in every iteration of the for loop. That is the problem. You will need to stop populating this variable after it has been successfully populated for the first find.

To do this, in the for loop do a test for iteration_time and only if it is non- existent or None do the regex search for Time. You can do soemthing like this:

contCumulative_0_out = open('contCumulative_0', 'w+')

with open(logFile, 'r') as logfile_read:
    iteration_time = None
    for line in logfile_read:
        line = line.rstrip()
        time_match = re.findall(r'^Time = ([0-9]+)', line)
        if time_match:
            iteration_time = time_match
            print iteration_time
        else:  # Because if there is time_match, there is no 'cumulative = ...'
            contCumulative_0 = re.search(r'cumulative = ((\d|.)+)', line)
            if contCumulative_0:        
                cumvalue = contCumulative_0.groups(1)
                # You can check and use iteration_time here
                contCumulative_0_out.write('\n'.join(cumvalue))

Hope this helps.