I have a textfile that consists of multiple blocks such as one shown here :
TestVar 00000000 WWWWWW 222.222 222.222 222.222 UNKNOWN ,,,,,,,, ,,,,,, ,,,,,, I would like to get the folowing output: Each part is always 8 characters long (e.g TestVar , 00000000) From each line that start with testvar i would like the code to return:
WWWWWW_00000000 Can someone help me with this I have used regex before but never with python and am quite new to both of them.
Thanks
assuming you dont want us to write the code for you here is a link that is quite specific http://docs.python.org/howto/regex.html#regex-howto
keep in mind you will likely want to use the findall()... and also write your code using r' instead of constantly needing the backslashes...
you might want to show us the code you wrote already and isnt working so we can help you better gl
With regex pattern ^TestVar\s+(\d{8})\s+(\S+) you can get that as >>
import re p = re.compile('^TestVar\s+(\d{8})\s+(\S+)') m = p.match('TestVar 00000000 WWWWWW 222.222 222.222 222.222') if m: print 'Match found: ', m.group(2) + '_' + m.group(1) else: print 'No match' Test this demo here.
To find all occurrences in multiline input string use:
p = re.compile("^TestVar\s+(\d{8})\s+(\S+)", re.MULTILINE) m = p.findall(input) To learn more about regex with Python, see http://docs.python.org/howto/regex.html
You mention multiple occurrences of the pattern, in which case you could use re.findall along with re.MULTILINE:
input_string = """ TestVar 00000000 WWWWWW 222.222 222.222 222.222 UNKNOWN ,,,,,,,, ,,,,,, ,,,,,, TestVar 22222222 AAAAAA 222.222 222.222 222.222 UNKNOWN ,,,,,,,, ,,,,,, ,,,,,, """ import re pat = re.compile("^TestVar\s+(\d{8})\s+(\S+)", re.MULTILINE) matches = pat.findall(input_string) # Result: matches == [('00000000', 'WWWWWW'), ('22222222', 'AAAAAA')] for num, let in matches: print "%s_%s" % (num, let) Without regexp:
lines = ["TestVar 00000000 WWWWWW 222.222 222.222 222.222", "UNKNOWN ,,,,,,,, ,,,,,, ,,,,,,"] print [toks[2].strip(' ')+'_'+toks[1] for toks in \ [[line[i:i+8] for i in xrange(0,len(line),8)] for line in lines] \ if toks[0] == 'TestVar '] 