Replacing Values with other values

[sjohri214]

Hi,

I hope someone can help me with the follwing problem?
it's a bit tricky to explain but ...

I have a file with the following data contained within it:

1 ODH_ARTSP,
2 DHLO_AGRVI,
3 ILV5_SPIOL,
4 MMSB_PSEAE,
5 6PGD_SHEEP
;
tree PAUP_1 = [&U] (1,(2,((3,5),4)));


Does anyone know how i can replace the digits in the the part of the file i.e. (1,(2,((3,5),4)));
with the corresponding text above it.
In order that i can end up with the following result:

(ODH_ARTSP,(DHLO_AGRVI,((ILV5_SPIOL,6PGD_SHEEP),MMSB_PSEAE)));

I have tried doing this replacement using Regular Expressions, but because I replace one by one it replaces the numbers in the replacement text as well so, ILV5_SPIOL becomes ILV6PGD_SHEEP_SPIOL because 6PGD_SHEEP is supposed to replace 5.

Does anyone have any idea of how i can go about doing this?

Any kind of help would be much appreciated

Thanks again

 

[HavaTheJut]

Use:

String str = "(1,(2,((3,5),4)))";
str.replaceAll("5","6PGD_SHEEP");

Or if you don't want to mess with other numbers containing 5 (like 25):

String str = "(1,(2,((3,5),4)))";
str.replaceAll("\\D5\\D","6PGD_SHEEP");

In java regex '\D' means non-digit, and '\\D' means place '\' into the string literal followed by 'D'.

 

[HavaTheJut]

Oops. The second of bit of code is incorrect, as replacing '\D5\D' with the value would elminate the two non-digits. Also, a 5 at the beginning or end of a string would be ignored. (It still feels like a Monday...)
To do this matching correctly, you can use the

java.util.regex

package:
(See

http://java.sun.com/j2se/1.4/docs/api/java/util/regex/Pattern.html

for java regex info)

String sNum = "5";
String sVal = "6PGD_SHEEP";
// add spaces to match digits at front and back
str = " "+str+" ";
// replace pattern
// \D5\D
String sRegex = "(\\D)"+sNum+"(\\D)";
// string to replace with
// $1 and $2 mean the values of group 1 and 2 - (\\D)
// these are added back to the replace string
String sRep = "$1"+sVal+"$2";
str.replaceAll(sRegex,sRep);
// trim the extra spaces
str = str.trim();

You can also use the regex package directly.

 

[sjohri214]

Hi HavaTheJut,

Thanks very much for the help, i was trying to find a way of referencing the captured groups using the m.group method, and didn't realise u could use the $1 method - (i thought this was restricted to Perl!)

Thanks again for your help
Much appreciated!!