Re: Replacing characters in a line

Hi, just try this,

$string='ATOM   3316  N   TYR D  24      97.479  18.805   2.990  1.00 
+36.32      D    N 
ATOM   3322  CD1 TYR D  24      96.225  15.974   2.812  1.00 17.96    
+  D    C';

$string=~s#((\w+)   \d{4}  \w   TYR )D#$1X#gsi;

print $string;

output:
*******
ATOM   3316  N   TYR X  24      97.479  18.805   2.990  1.00 36.32    
+  D    N
ATOM   3322  CD1 TYR D  24      96.225  15.974   2.812  1.00 17.96    
+  D    C
[download]

Comment on Re: Replacing characters in a line Download Code

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Re^2: Replacing characters in a line by holli (Abbot) on Mar 04, 2005 at 12:45 UTC
Why not just `s/(?<=TYR )D/X/;`? Update: Or, to keep it fixed-length: `s/^(.{21})D/$1X/;` [download] Sidenote: Has anyone an idea, why this: `s/^(?<=.{21})D/X/;` [download] does not work, while this `s/(?<=.{21})D/X/;` [download] does (but don´t use this, it´s unsafe)? holli, /regexed monk/	[reply] [d/l] [select]
Re^3: Replacing characters in a line by manav (Scribe) on Mar 04, 2005 at 13:19 UTC
Are we sure that D will always be preceeded by "TYR " ?? Manav	[reply]
Re^4: Replacing characters in a line by holli (Abbot) on Mar 04, 2005 at 13:32 UTC
We can only tell from the example data. pelagic's regex is also unsafe. what if the line looks like `ATOM 3316 N TYR B 24 97.479 18.805 2.990 1.00 36.32 + D N` [download] Then the alone "D" at the end will be replaced by "X". Intended?? I would use the substr()-solution above. My regex was just meant as an optimization of perlsen's one, which is unneccesary complicated. Update: Striked the sillyness about the second "D". /me writes "Must read the question properly" 200 times. holli, /regexed monk/	[reply] [d/l]
Re^4: Replacing characters in a line by pelagic (Priest) on Mar 04, 2005 at 13:23 UTC
We are not! As the OP stated: there are two D's on every line. pelagic	[reply]


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