Python

read & print only first & last line of txt file

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read & print only first & last line of txt file

Apr 29th, 2008

Hi all, hope you are well. Just a quick one here that you pythons will be able to answer in no time (I am new with python). What I am trying to do is read a text file and print only the first and last line of that file. Any ideas as to how I might go about this ? I have read the file so all i need to do is find a way of finding out which is first and last line, and then printing them. Thanks for your time.

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Re: read & print only first & last line of txt file

Apr 29th, 2008

Ok I have now established how to print the last line of a text file. Anyone interested here is where I found the answer:

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http://www.daniweb.com/forums/showth...int+first+line

I still need to figure out how to print the first line of the text file, so any ideas on this are welcome!

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Re: read & print only first & last line of txt file

Apr 29th, 2008

ok ignore the above link - it is a search link which doesnt seem to work. Here is the solution that I have worked out:

 Help with Code Tags 
 python Syntax (Toggle Plain Text) 
def lab01():
    file = open('filename.txt','r')#specify file to open
    data = file.readlines() #read lines in file and put 
    #into LIST called data
    print "Last line = "
    print data[len(data)-1] #-1 represents last item on list data
    print "First line = "
    file.seek ( 0 )#seek to first line in file
    print file.readline()
    file.close() #good practice to close files after use
def lab01():
    file = open('filename.txt','r')#specify file to open
    data = file.readlines() #read lines in file and put 
    #into LIST called data
    print "Last line = "
    print data[len(data)-1] #-1 represents last item on list data
    print "First line = "
    file.seek ( 0 )#seek to first line in file
    print file.readline()
    file.close() #good practice to close files after use

Last edited by majestic0110; Apr 29th, 2008 at 12:09 pm.

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Re: read & print only first & last line of txt file

Apr 29th, 2008

Restructured the code to make it a little more elegant now:

 Help with Code Tags 
 python Syntax (Toggle Plain Text) 
def lab01():
    file = open('swift20080428172404.txt','r')#specify file to open
    data = file.readlines() #read lines in file and put into 
    #LIST called data
    file.close() #good practice to close files after use
    print "Last line = "
    print data[len(data)-1] #-1 represents last item on list data
    print "First line = "
    print data[0] #-1 represents last item on list data
def lab01():
    file = open('swift20080428172404.txt','r')#specify file to open
    data = file.readlines() #read lines in file and put into 
    #LIST called data
    file.close() #good practice to close files after use
    print "Last line = "
    print data[len(data)-1] #-1 represents last item on list data
    print "First line = "
    print data[0] #-1 represents last item on list data