[Tutor] String Attribute

[Ltc Hotspot]

Hi Alan,

Question1: The output result is an address or line?
Question2: Why are there 54 lines as compared to 27 line in the desired
output?

Here is the latest revised code:
fname = raw_input("Enter file name: ")
if len(fname) < 1 : fname = "mbox-short.txt"
fh = open(fname)
count = 0
addresses = set()
for line in fh:
    if line.startswith('From'):
        line2 = line.strip()
        line3 = line2.split()
        line4 = line3[1]
        addresses.add(line4)
        count = count + 1
print addresses
print "There were", count, "lines in the file with From as the first word"

The output result:
set(['stephen.marquard at uct.ac.za', 'louis at media.berkeley.edu', '
zqian at umich.edu', 'rjlowe at iupui.edu', 'cwen at iupui.edu', 'gsilver at umich.edu',
'wagnermr at iupui.edu', 'antranig at caret.cam.ac.uk', '
gopal.ramasammycook at gmail.com', 'david.horwitz at uct.ac.za', '
ray at media.berkeley.edu']) ← Mismatch
There were 54 lines in the file with From as the first word


The desired output result:
stephen.marquard at uct.ac.za
louis at media.berkeley.edu
zqian at umich.edu
rjlowe at iupui.edu
zqian at umich.edu
rjlowe at iupui.edu
cwen at iupui.edu
cwen at iupui.edu
gsilver at umich.edu
gsilver at umich.edu
zqian at umich.edu
gsilver at umich.edu
wagnermr at iupui.edu
zqian at umich.edu
antranig at caret.cam.ac.uk
gopal.ramasammycook at gmail.com
david.horwitz at uct.ac.za
david.horwitz at uct.ac.za
david.horwitz at uct.ac.za
david.horwitz at uct.ac.za
stephen.marquard at uct.ac.za
louis at media.berkeley.edu
louis at media.berkeley.edu
ray at media.berkeley.edu
cwen at iupui.edu
cwen at iupui.edu
cwen at iupui.edu
There were 27 lines in the file with From as the first word

Regards,
Hal









On Sat, Aug 1, 2015 at 1:40 PM, Alan Gauld <alan.gauld at btinternet.com>
wrote:

> On 01/08/15 19:48, Ltc Hotspot wrote:
>
>> There is an indent message in the revised code.
>> Question: Where should I indent the code line for the loop?
>>
>
> Do you understand the role of indentation in Python?
> Everything in the indented block is part of the structure,
> so you need to indent everything that should be executed
> as part of the logical block.
>
> fname = raw_input("Enter file name: ")
>> if len(fname) < 1 : fname = "mbox-short.txt"
>> fh = open(fname)
>> count = 0
>> addresses = set()
>> for line in fh:
>>      if line.startswith('From'):
>>      line2 = line.strip()
>>      line3 = line2.split()
>>      line4 = line3[1]
>>      addresses.add(line)
>>      count = count + 1
>>
>
> Everything after the if line should be indented an extra level
> because you only want to do those things if the line
> startswith From.
>
> And note that, as I suspected, you are adding the whole line
> to the set when you should only be adding the address.
> (ie line4). This would be more obvious if you had
> used meaningful variable names such as:
>
>     strippedLine = line.strip()
>     tokens = strippedLine.split()
>     addr = tokens[1]
>     addresses.add(addr)
>
> PS.
> Could you please delete the extra lines from your messages.
> Some people pay by the byte and don't want to receive kilobytes
> of stuff they have already seen multiple times.
>
>
> --
> Alan G
> Author of the Learn to Program web site
> http://www.alan-g.me.uk/
> http://www.amazon.com/author/alan_gauld
> Follow my photo-blog on Flickr at:
> http://www.flickr.com/photos/alangauldphotos
>
>