* Re: how to drop the nth element of a list
@ 1991-10-18 19:31 Byron Rakitzis
0 siblings, 0 replies; 4+ messages in thread
From: Byron Rakitzis @ 1991-10-18 19:31 UTC (permalink / raw)
To: rc
You can do this in at most the cost of 3 forks and 2 execs; suppose that
$foo contains the list you want to operate on, and $n contains the number
of the element you wish to remove:
foo=$foo(`{seq 1 $#foo | grep -v '^'$n'$'})
You could also probably do the stuff in backquotes in a single awk job,
but it involves more messing around with quotes, and takes longer to
type. Still, it will run faster:
awk 'BEGIN{
for (i = 1; i < '$#foo'; i++)
if (i != '$n')
print i
exit
}'
Packaging this into an rc function is left as an excercise for the
reader...
^ permalink raw reply [flat|nested] 4+ messages in thread
* Re: how to drop the nth element of a list
@ 1991-10-18 19:48 Rich Salz
0 siblings, 0 replies; 4+ messages in thread
From: Rich Salz @ 1991-10-18 19:48 UTC (permalink / raw)
To: byron, rc
I don't have seq. This seems to work okay:
x=(a b c d e f)
n=3
{ for (i in $x ) echo $i } | sed -e $n^d
a
b
d
e
^ permalink raw reply [flat|nested] 4+ messages in thread
* Re: how to drop the nth element of a list
@ 1991-10-18 19:42 DaviD W. Sanderson
0 siblings, 0 replies; 4+ messages in thread
From: DaviD W. Sanderson @ 1991-10-18 19:42 UTC (permalink / raw)
To: rc
> Packaging this into an rc function is left as an excercise for the
> reader...
One (simple) solution is the 'chop' function I contributed to the
rc 1.2 EXAMPLES file.
DaviD Sanderson (dws@cs.wisc.edu)
^ permalink raw reply [flat|nested] 4+ messages in thread
* how to drop the nth element of a list
@ 1991-10-18 16:38 malte
0 siblings, 0 replies; 4+ messages in thread
From: malte @ 1991-10-18 16:38 UTC (permalink / raw)
To: rc
Does anyone have a good idea to drop the nth element from a list?
I can only think of something using head(1) and tail(1), which is
not too efficient.
_______________________________________________________________________________
malte@techfak.uni-bielefeld.de
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^ permalink raw reply [flat|nested] 4+ messages in thread
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