On 04/30/2012 05:24 PM, deltaquat...@gmail.com wrote: > Hi, > > I would like to automate some simple tasks I'm doing by hand. Given a text > file > foobar.fo: > > 073 1.819 > 085 2.132 > 100 2.456 > 115 2.789 > > I need to create the directories 073, 085, 100, 115, and copy in each > directory a modified version of the text file input.in: > > . > . > . > foo = 1.5 ! edit this value > . > . > . > bar = 1.5 ! this one, too > . > . > . > > Tthe modification consists in substituting the number in the above lines with > the value associated to the directory in the file foobar.fo. Thus, the > input.in file in the directory 100 will be: > > . > . > . > foo = 2.456 ! edit this value > . > . > . > bar = 2.456 ! this one, too > . > . > . > > At first, I tried to write a bash script to do this. However, when and if the > script will work, I'll probably want to add more features to automate some > other tasks. So I thought about using some other language, to have a more > flexible and mantainable code. I've been told that both Python and perl are > well suited for such tasks, but unfortunately I know neither of them. Can you > show me how to write the script in Python? Thanks,
Perhaps something like this will get you started? To keep things simple (since this is illustrative code) there is little parameterization and no error handling. Apologies if Google screws up the formatting too bad. -------------------------------------------------------- from __future__ import print_function #1 import os def main(): listf = open ('foobar.fo') for line in listf: dirname, param = line.strip().split() #7 make_directory (dirname, param) def make_directory (dirname, param): os.mkdir (dirname) #11 tmplf = open ("input.in") newf = open (dirname + '/' + 'input.in', 'w') #13 for line in tmplf: if line.startswith ('foo = ') or line.startswith ('bar = '): #15 line = line.replace (' 1.5 ', ' '+param+' ') #16 print (line, file=newf, end='') #17 if __name__ == '__main__': main() #19 ------------------------------------------------------------ #1: Not sure whether you're using Python 2 or 3. I ran this on Python 2.7 and think it will run on Python 3 if you remove this line. #7:The strip() method removes the '\n' characters from the end of the lines as well as any other extraneous leading or trailing whitespace. The split() method here breaks the line into two pieces on the whitespace in the middle. See http://docs.python.org/library/stdtypes.html#string-methods #11: This will create subdirectory 'dirname' relative to the current directory of course. See http://docs.python.org/library/os.html#os.mkdir #13: Usually, is is more portable to use os.path.join() to concatenate path components but since you stated you are on Linux (and "/" works on Windows too), creating the path with "/" is easier to follow in this example. For open() see http://docs.python.org/library/functions.html#open #15: Depending on your data, you might want to use the re (regular expression) module here if the simple string substitution is not sufficient. #16: For simplicity I just blindly replaced the " 1.5 " text in the string. Depending of your files, you might want to parameterize this of do something more robust or sophisticated. #17: Since we did not strip the trailing '\n' of the lines we read from "input.in", we use "end=''" to prevent print from adding an additional '\n'. See http://docs.python.org/library/functions.html#print #19: This line is required to actually get your python file to do anything. :-) Hope this gets you started. I think you will find doing this kind of thing in Python is much easier in the long run than with bash scripts. A decent resource for learning the basics of Python is the standard Python tutorial: http://docs.python.org/tutorial/index.html -- http://mail.python.org/mailman/listinfo/python-list