Re: Re: how to select column

[mannu jha]

Dear Sir,

Thanks for your help..........but yes my files are having column like:

#  RESIDUE AA STRUCTURE BP1 BP2  ACC     N-H-->O    O-->H-N    N-H-->O    O-->H-N    TCO  KAPPA ALPHA  PHI   PSI    X-CA   Y-CA   Z-CA 
    1    2 A I              0   0   91      0, 0.0    38,-0.1     0, 0.0     5,-0.0   0.000 360.0 360.0 360.0 156.1   38.1   24.6   -5.0
    2    3 A R    >>  -     0   0   86      1,-0.1     4,-1.8    38,-0.1     3,-1.0  -0.377 360.0-116.9 -66.2 144.2   35.1   25.2   -7.3
    3    4 A P  H 3> S+     0   0   81      0, 0.0     4,-2.7     0, 0.0     5,-0.2   0.843 111.7  60.4 -55.3 -36.8   34.6   28.8   -8.2

and in the output I want just:
2 A I
3 A R    >>  -
4 A P  H 3> S+

i.e. residue no., aa and seconday structure.

Thanks
 

On Mon, 26 Apr 2010 20:40:55 +0530  wrote
>mannu jha wrote:

> Dear all,

>

> I am new in python, can anyone help me that how can I select two 

> column out of 6 column from a file.

> For example if I have file like:

>

> a1 a2 a3 a4 a5 a6

> b1 b2 b3 b4 b5 b6

> c1 c2 c3 c4 c5 c6

> d1 d2 d3 d4 d5 d6

>

> and I want output like:

>

> a1 a4

> b1 b4

> c1 c4

> d1 d4

>

> then how to do

>

> Thanks 





Do you know how to open a file, and how to read individual lines from it?



If so, then you can split a line at the spaces into a list by using

 fields = line.split()

Then

 print fields[0], fields[3]

would do what you ask.







Gary Herron







-- 

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