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how to get no value

Hi,

I have a file having lines:-

48 ALA H = 8.33 N = 120.77 CA = 55.18 HA = 4.12 C = 181.50
104 ALA H = 7.70 N = 121.21 CA = 54.32 HA = 4.21 C =
85 ALA H = 8.60 N =  CA =  HA = 4.65 C =

Now i want to make two another file in which i want to put those lines for
which C is missing and another one for which N,CA and C all are missing,

I tried in this way:
import re
f = open('chem.txt')
for line in f:
     if re.search('C = ',''):
        print line

but i am not getting the desired output.




Amrita Kumari
Research Fellow
IISER Mohali
Chandigarh
INDIA

0
amrita (13)
7/24/2009 10:20:11 AM
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amrita@iisermohali.ac.in schrieb:
> Hi,
> 
> I have a file having lines:-
> 
> 48 ALA H = 8.33 N = 120.77 CA = 55.18 HA = 4.12 C = 181.50
> 104 ALA H = 7.70 N = 121.21 CA = 54.32 HA = 4.21 C =
> 85 ALA H = 8.60 N =  CA =  HA = 4.65 C =
> 
> Now i want to make two another file in which i want to put those lines for
> which C is missing and another one for which N,CA and C all are missing,
> 
> I tried in this way:
> import re
> f = open('chem.txt')
> for line in f:
>      if re.search('C = ',''):
>         print line
> 
> but i am not getting the desired output.


Gosh. Must be groundhog-day. Again.

And there is me thinking that my job could be endangered by cheap & 
qualified indian soft-workers - can't be to many of them around if the 
OP doesn't get a hold of one for the better part of a month now. Must be 
one of those management myths they tell you to scare you into a less 
well paid contract...

Diez
0
deets (3351)
7/24/2009 10:56:16 AM
>>>>> amrita@iisermohali.ac.in (a) a �crit:

>a> Hi,

>a> I have a file having lines:-

>a> 48 ALA H = 8.33 N = 120.77 CA = 55.18 HA = 4.12 C = 181.50
>a> 104 ALA H = 7.70 N = 121.21 CA = 54.32 HA = 4.21 C =
>a> 85 ALA H = 8.60 N =  CA =  HA = 4.65 C =

>a> Now i want to make two another file in which i want to put those lines for
>a> which C is missing and another one for which N,CA and C all are missing,

>a> I tried in this way:
>a> import re
>a> f = open('chem.txt')
>a> for line in f:
>a>      if re.search('C = ',''):
>a>         print line

>a> but i am not getting the desired output.

You never look in the lines you read. 
    if re.search('C = ',''): should be
    if re.search('C = ', line):

Do you really think before you write your code? Or look at it after you
have written it? 

Sorry if I offend you but you give the impression of just trying some
more or less random stuff and then asking here if it doesn't give the
required result.

That's not the attitude of a researcher, unless your definition of
research is 'asking on Usenet'.
-- 
Piet van Oostrum <piet@cs.uu.nl>
URL: http://pietvanoostrum.com [PGP 8DAE142BE17999C4]
Private email: piet@vanoostrum.org
0
piet27 (1059)
7/24/2009 11:48:09 AM
On 2009-07-24, amrita@iisermohali.ac.in <amrita@iisermohali.ac.in> wrote:
>
> Hi,
>
> I have a file having lines:-
>
> 48 ALA H = 8.33 N = 120.77 CA = 55.18 HA = 4.12 C = 181.50
> 104 ALA H = 7.70 N = 121.21 CA = 54.32 HA = 4.21 C =
> 85 ALA H = 8.60 N =  CA =  HA = 4.65 C =
>
> Now i want to make two another file in which i want to put
> those lines for which C is missing and another one for which
> N,CA and C all are missing,
>
> I tried in this way:
> import re
> f = open('chem.txt')
> for line in f:
>      if re.search('C = ',''):
>         print line
>
> but i am not getting the desired output.

I've told you before: don't use regular expressions (e.g. the
"re" module).  Stop using regular expressions now.  Regular
expressions are way beyond your capabilities.  

Use simple operations like split() and "in":

  f = open('chem.txt')
  for line in f:
    if "C = " in line:
      print line
      
You really need to work through a Python tutorial or two:

  http://docs.python.org/tutorial/
  http://www.greenteapress.com/thinkpython/thinkpython.html

Better yet, take an couple introductory programming courses.

I'm a bit surprised that one could become a "Research Fellow"
in a scientific field without taking any programming courses.

-- 
Grant Edwards                   grante             Yow! I'm also against
                                  at               BODY-SURFING!!
                               visi.com            
0
Grant
7/24/2009 2:10:29 PM
Well actually your subject is `how to get no value'. Your code does that
perfectly. :=)
-- 
Piet van Oostrum <piet@cs.uu.nl>
URL: http://pietvanoostrum.com [PGP 8DAE142BE17999C4]
Private email: piet@vanoostrum.org
0
piet27 (1059)
7/24/2009 3:06:23 PM
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