switching array entries

hotshot has asked for the wisdom of the Perl Monks concerning the following question:

is there a short way to move an element in an array. my function gets as arguments indexFrom and indexTo and I want to move the indexFrom entry to indexTo and ordering the array as necessary, for example:

my @array = qw(one two three four five six seven);

@newArray = myFunc(\@array, 4, 1);
print join(', ', @newArray);

# should give us:
one, five, two, three, four, six, seven
[download]

as we can see the entry move to the desired location and the rest of the array shifted a little (BTW, the entry can move forward also).

Thanks

Hotshot

Comment on switching array entries Download Code

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Re: switching array entries by zigdon (Deacon) on Oct 30, 2002 at 14:08 UTC
You're probably looking for the splice function: `my @array = qw(one two three four five six seven); splice(@array,1,0,$array[4]); # add the item to the new position splice(@array,5,1); # remove it from it's old position (note the moved + index) print "@array"'` [download] There's probably a cool way to do this in one shot. Update: and there is a cool way to do it! see mce's reply. -- Dan	[reply] [d/l]
Re: switching array entries by mce (Curate) on Oct 30, 2002 at 14:14 UTC
Hi, ++zigdon, You can even do it on one go. `splice(@array,1,0,splice(@array,4,1) );` [download] cool he, --------------------------- Dr. Mark Ceulemans Senior Consultant IT Masters, Belgium	[reply] [d/l]
Re: Re: switching array entries by hotshot (Prior) on Oct 30, 2002 at 14:46 UTC
thanks for your answer, but pay attentions that if $indexFrom is smaller than $indexTo, we have to susbstruct 1 in the the outer splice's offset. Hotshot	[reply]
Re: switching array entries by robartes (Priest) on Oct 30, 2002 at 14:33 UTC
Or, in yet another way to do it, and assuming variable indexTo means the index position before the move (i.e. indexTo=4 means in front of the element that was the element with index 4 before the move): `splice(@array,$indexTo-($indexTo>$indexFrom),0,splice(@array,$indexFro +m,1));` [download] CU Robartes-	[reply] [d/l]
Re: switching array entries by artist (Parson) on Oct 30, 2002 at 15:23 UTC
I looked at two different approach: $p1 = 1; $p2 = 4; `splice(@array,$p1+1,0,splice(@array,$p1,$p2-1));` [download] AND `splice(@array,$p1,0,splice(@array,$p2,$p1) );` [download] The second approach involves less 'moving'. Artist	[reply] [d/l] [select]