Replacement of a substring in a string

hariibm · New User Joined: 05 Feb 2007 Posts: 61 Location: Chennai

Hi,

I would like to replace a substring in a String with another substring.

Ex: 145 143 142 + 1422
suppose i want to replace 142 with 152, then the result string after replacemnet is :
145 143 152 + 1422

i.e it must change the substring only 142 by 152. but not 1422 to 152.
Please provide me a piece of code for the above requirement.
Please let me know if it is not clear.

Hari

hariibm · New User Joined: 05 Feb 2007 Posts: 61 Location: Chennai

a small correction ..
1422 must not be changed to 1522. only the exact string ie. 142 must be changed to 152.

enrico-sorichetti · Posted: Wed Jul 23, 2008 2:27 pm

give a proper definition of string/substring ...

as a general point , given the topic title, both strings should be substituted,
in your case the thing to be substituted should be named something like
"blank delimited thing"
but, what if there is no blank between the 142 and the +

the parsing algorithm would get a bit more complicated...

I assumed a completely unformatted thing, here is a bit of logic

position on the first char after the first delimiter
( or at the beginning of the string )

find the next delimiter
check the length of the field
if equal check the substring
carry on the substitution ( in place or ... )

position on the char after the found delimiter...
loop

hariibm · New User Joined: 05 Feb 2007 Posts: 61 Location: Chennai

145 143 142 + 1422 is a string.
and 142 is the substring. the substring 142 is to be replaced by 152.
the next character after 142 must not be a digit. it can be space or + or - or /(totally 5 such chars). whichever of the above, the replacement should be done.

ashimer · Posted: Wed Jul 23, 2008 2:36 pm

hariibm · New User Joined: 05 Feb 2007 Posts: 61 Location: Chennai

Hi ashimer,
I can not use INSPECT because the lengths of old substring(to be replaced) and new substrings are not known. it can be replacement of 3 characters by 5 or 5 characters by 3 etc.

ashimer · Posted: Wed Jul 23, 2008 2:41 pm

ok .. i didnt see your second post ... can you please post all the occurences and the expected o/p ?

enrico-sorichetti · Posted: Wed Jul 23, 2008 2:43 pm

hariibm · New User Joined: 05 Feb 2007 Posts: 61 Location: Chennai

Hi enrico-sorichetti,
If the string is 145 143 9142 + 1422
and if I want to replace 142 by 152 in the above case, no replacement must be done since there is no 142 as 142 and 9142 represent different IDs.
The replacement algorithm must find the exact match and replace it with the new substring.

enrico-sorichetti · Posted: Wed Jul 23, 2008 2:58 pm

since we are talking about string/substring substitution

I ask again what are the front/starting delimiters ?

You told about the termination delimiter
for parsing You must tell also the starting delimiter

they might be different ID's ( applcation terminology, not parsing )
still by the way You expressed Yor requirement ( termination only constraint )
my sample was correct given the wrong/lack_of information
are we dealing with full free form strings ??

hariibm · New User Joined: 05 Feb 2007 Posts: 61 Location: Chennai

Hi ashimer,

Please find below various cases.
first line represents the actual string and the next line represents the string after replacement.

Assuming 142 is to be replaced by 152.
1. 145 143 142 + 1422
145 143 152 + 1422

2. 145 143 /142 + 1422
145 143 /152 + 1422

3. 145 143 -142 + 1422
145 143 -152 + 1422

4. 145 143 141 + 1422
145 143 141 + 1422 (since there is no match hence there is no replacement.)

Assuming 142 is to be replaced by 1423.

5. 145 143 142 + 1422
145 143 1423 + 1422

6. 145 143 142/ + 1422
145 143 1423/ + 1422

Assuming 1432 is to be replaced by 143.

7. 145 +1432 142 + 1422
145 +143 142 + 1422

hariibm · New User Joined: 05 Feb 2007 Posts: 61 Location: Chennai

Hi enrico-sorichetti,
The possible delimiters are +, -, /, ;, # or space.
They appear both at the front and at the end.

enrico-sorichetti · Posted: Wed Jul 23, 2008 3:16 pm

Parsing in cobol s not easy,
what is the source of Your data , would it be a viable solution to try to get it in a fixed format ??

anyway here is a pointer to an article about parsing in cobol ( uses reference modification )
http://www.simotime.com/cblrmp01.htm
very good to get an idea about parsing in cobol,
does not do exactly what You are asking for, but extrapolation should be easy
beware of the legal/copyright issues before using

hariibm · New User Joined: 05 Feb 2007 Posts: 61 Location: Chennai

If I know the exact location where the replacement should be done, then let me know how to replace it with a new substring and form a new string.

ashimer · Posted: Wed Jul 23, 2008 6:25 pm

hari,

here is an example of changing 142 to 152 ... work on it for all cases ..