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From: flee@SHIRE.CS.PSU.EDU (Felix Lee)
Newsgroups: comp.lang.icon
Subject: Re: deleting characters
Message-ID: <9001200007.AA02947@shire.cs.psu.edu>
Date: 20 Jan 90 00:07:40 GMT
References: <9001192303.AA01299@zk.cray.com>
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> It turns out that the IPL delete routine was the slowest, although
> the fastest was only 15 percent faster.

On pathological cases, the delete routine can be much slower.  Try
removing spaces from repl("a   ", 1000).

The delete routine is quadratic wrt the length of the source string,
while the strip routines are quadratic wrt the result.  This is due
to the terrible amount of copying involved in manipulating Icon
strings: delete has to copy 3997 + 3994 + ... + 1000 characters,
while the other procedures need only copy 1 + 2 + ... + 1000.

You can get linear performance if you do it in C.
--
Felix Lee	flee@shire.cs.psu.edu	*!psuvax1!flee