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Problem in extracting vector data

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Thread: Problem in extracting vector data

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#2 (permalink)

03-18-2008

era

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Please add some more hints. Is file B always a single line? Do you want to do this in the Enterprise Silver Platinum Mojo Beans way or just a one-off job?

Code:

sed -e 's/.*/s%^.*\\(<[^<>]*>\\).*%\\1 \* &%/' fileB | sed -f - fileA

In the famous words of Dennis M. Ritchie, You Are Not Supposed to Understand This.

Actually, as a brief overview, we are taking the contents of fileB (presumably a single line) and wrapping it inside some sed commands, which are then passed as a script to sed to run on fileA. Conveniently, the first sed writes a script for the second containing the contents of fileB and a bit of sed trickery. It's not even tricky at all, once you wrap your head around it (and decode the escapes needed to prevent the literal parts in the first script from being interpreted by the first sed).

Last edited by era; 03-18-2008 at 03:23 AM.. Reason: I forgot to add a plus on all lines but the first, but maybe that can be left as an exercise ...