Re: [PHP] strip out repeated ocurrence of a string
On 1/25/2010 10:48 PM, Camilo Sperberg wrote:
Hello list :)
I have this problem, a certain string can contain the following information:
$string = '
hi{value1;value2}
bye{value1;value3}
hi{value1;value4}
hi{value1;value2}
bye{value1;value2}
';
What I want is to be able to get this result:
$string = '
hi{value1;value2}
bye{value1;value3}
hi{value1;value4}
bye{value1;value2}
';
(the order of appearance doesn't matter)
Is it even possible to do this with regular expressions? Or should I first
look if there is some kind of match and then apply an
str_replace($match,'',$string) and add the $match again?
Greetings !
Assuming the duplicate segments are identical.
I'd use explode() and convert the string to an array. Use } for the delimiter.
Then use array_unique()
And then use implode() to restore the string.
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Re: [PHP] strip out repeated ocurrence of a string
On Tue, 2010-01-26 at 07:56 -0500, Al wrote:
On 1/25/2010 10:48 PM, Camilo Sperberg wrote:
Hello list :)
I have this problem, a certain string can contain the following information:
$string = '
hi{value1;value2}
bye{value1;value3}
hi{value1;value4}
hi{value1;value2}
bye{value1;value2}
';
What I want is to be able to get this result:
$string = '
hi{value1;value2}
bye{value1;value3}
hi{value1;value4}
bye{value1;value2}
';
(the order of appearance doesn't matter)
Is it even possible to do this with regular expressions? Or should I first
look if there is some kind of match and then apply an
str_replace($match,'',$string) and add the $match again?
Greetings !
Assuming the duplicate segments are identical.
I'd use explode() and convert the string to an array. Use } for the
delimiter.
Then use array_unique()
And then use implode() to restore the string.
Just did a bit of hunting as I know I've seen something similar to what
you're asking before.
If you're on a Linux system, try this:
awk '!x[$0]++' inputfile outputfile
This seems to be the best way to remove duplicate lines and still
preserve the original order of the unique lines.
Thanks,
Ash
http://www.ashleysheridan.co.uk
Re: [PHP] strip out repeated ocurrence of a string
a certain string can contain the following information:
$string =
'hi{value1;value2}bye{value1;value3}hi{value1;value4}hi{value1;value2}bye{value1;value2}';
What I want is to be able to get this result:
$string =
'hi{value1;value2}bye{value1;value3}hi{value1;value4}bye{value1;value2}';
(the order of appearance doesn't matter)
Assuming the duplicate segments are identical.
I'd use explode() and convert the string to an array. Use } for the
delimiter.
Then use array_unique()
And then use implode() to restore the string.
Really nice solution indeed :D I didn't know array_unique() (well, that's
not entirely true, I had read about it once or twice, but didn't remembered
it).
Anyway, I remembered after I sended the mail that the order DO matter, but
that is just reversing an array :)
Just for the record, the applied code is:
$string =
implode('}',array_reverse(array_unique(array_reverse(explode('}',$string);
First, an explode of the string to create an array, than I reverse it so
that the last ocurrence of the repeated part will always be last, after that
I apply array_unique, de-reverse it and implode it all back together as a
string.
Result?
input:
hi{value1;value2}bye{value1;value3}hi{value1;value4}hi{value1;value2}bye{value1;value2}
output:
bye{value1;value3}hi{value1;value4}hi{value1;value2}bye{value1;value2}
Thank you very much !
@Ashley: It must be done in PHP, because it should run in any environment.
But thanks anyway, any help is apreciated: you just saw that there was a
much easier way than trying to use regular expressions or str_replace when
using arrays is considerably faster (especially because the $string won't be
a few bytes, it could range from ~5 bytes up to ~300+ KiB).
Greetings!
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ICQ #: 54472056
www1: http://www.chw.net/
www2: http://unreal4u.com/
[PHP] strip out repeated ocurrence of a string
Hello list :)
I have this problem, a certain string can contain the following information:
$string = '
hi{value1;value2}
bye{value1;value3}
hi{value1;value4}
hi{value1;value2}
bye{value1;value2}
';
What I want is to be able to get this result:
$string = '
hi{value1;value2}
bye{value1;value3}
hi{value1;value4}
bye{value1;value2}
';
(the order of appearance doesn't matter)
Is it even possible to do this with regular expresions? Or should I first
look if there is some kind of match and then apply an
str_replace($match,'',$string) and add the $match again?
Greetings !
--
Mailed by:
UnReAl4U - unreal4u
ICQ #: 54472056
www1: http://www.chw.net/
www2: http://unreal4u.com/
