Re: How to delete multiple indices from array

Thanks for your reply. First of all, my example was not about performance, but was about an idea. So you are correct about qw and sort. I'm sorry if someone saw this example and decide to use it without reading perldoc and understanding what we do. We need to reverse sort because when we

Re: How to delete multiple indices from array

On Wed, 12 Apr 2017 19:34:22 -0400 Uri Guttman wrote: > it is so odd to be filtering an array by the indexes. i smell an XY > problem here. i wonder what the real goal is vs how to solve it this > way. > > thanx, > > uri I was thinking that too. -- Don't stop where

Re: How to delete multiple indices from array

On 04/12/2017 07:29 PM, Shawn H Corey wrote: On Wed, 12 Apr 2017 18:16:56 -0400 Uri Guttman wrote: It's not about saving time. It's about removing a bug. In the code below, notice that there are two different outputs depending on the order that splice is applied. It's

Re: How to delete multiple indices from array

On Wed, 12 Apr 2017 18:16:56 -0400 Uri Guttman wrote: > On 04/12/2017 05:42 PM, Shawn H Corey wrote: > > On Wed, 12 Apr 2017 16:19:32 -0400 > > Uri Guttman wrote: > > > > > > my @array; > > > > for my $index (reverse sort @indices) { > >> sort

Re: How to delete multiple indices from array

On 04/12/2017 05:42 PM, Shawn H Corey wrote: On Wed, 12 Apr 2017 16:19:32 -0400 Uri Guttman wrote: my @array; for my $index (reverse sort @indices) { sort defaults to a lexical sort which won't work well on integers with more than 2 digits. and why are you sorting and

Re: How to delete multiple indices from array

Quite! Even the slowest may find redemption in clarity :) my @arr = qw( zero one two three ... ); my @del = qw( 2,4,... ); my( %del, @new ); @del{ @del } = (); for (0..$#arr) { push @new, $arr[$_] unless exists $del{$_}} On Wed, Apr 12, 2017 at 2:18 PM, Paul Johnson wrote: > On

Re: How to delete multiple indices from array

On Wed, 12 Apr 2017 16:19:32 -0400 Uri Guttman wrote: > On 04/12/2017 04:08 PM, Илья Рассадин wrote: > > Hi! > > > > You can use splice to delete elements from array. > > > > To delete multiple elements you need to do splice in a loop > > > > my @indices = qw/2 4 5 7/; > >

Re: How to delete multiple indices from array

On Wed, Apr 12, 2017 at 11:12:45PM +0200, David Emanuel da Costa Santiago wrote: > Thank you all for your replies. > > I tested the 5 solutions with the benchmark module, and the splice one > is the fastest: > The hash one, which was my first solution is the slowest one. :-( But they're all

Re: How to delete multiple indices from array

Thank you all for your replies. I tested the 5 solutions with the benchmark module, and the splice one is the fastest: Benchmark: timing 99 iterations of each, grep, hash, keep, splice... each: 5 wallclock secs ( 5.07 usr + 0.00 sys = 5.07 CPU) @ 197238.46/s (n=99) grep: 5

Re: How to delete multiple indices from array

On 04/12/2017 04:38 PM, Shlomi Fish wrote: Hi Uri! Some notes. On Wed, 12 Apr 2017 15:19:33 -0400 Uri Guttman wrote: On 04/12/2017 03:00 PM, David Emanuel da Costa Santiago wrote: Hello! What's the best way to delete multiple indices from an array? i'm doing:

Re: How to delete multiple indices from array

Hi Uri! Some notes. On Wed, 12 Apr 2017 15:19:33 -0400 Uri Guttman wrote: > On 04/12/2017 03:00 PM, David Emanuel da Costa Santiago wrote: > > Hello! > > > > What's the best way to delete multiple indices from an array? > > > > i'm doing: > > > > --- > > my

Re: How to delete multiple indices from array

On 04/12/2017 04:08 PM, Илья Рассадин wrote: Hi! You can use splice to delete elements from array. To delete multiple elements you need to do splice in a loop my @indices = qw/2 4 5 7/; why are you using qw which makes strings and not a list of integers? my @array; for my $index

Re: How to delete multiple indices from array

Hi! You can use splice to delete elements from array. To delete multiple elements you need to do splice in a loop my @indices = qw/2 4 5 7/; my @array; for my $index (reverse sort @indices) { splice @array, $index, 0; } 12.04.17 22:19, Uri Guttman пишет: On 04/12/2017 03:00 PM,

Re: How to delete multiple indices from array

On 04/12/2017 04:01 PM, David Emanuel da Costa Santiago wrote: Thanks for your reply. I didn't think about that! :-) While i was reading your email, i remembered about splice, so i guess i'm going to end up with: -- my @array=qw/zero one two three four five six seven eight nine ten/;

Re: How to delete multiple indices from array

Thanks for your reply. I didn't think about that! :-) While i was reading your email, i remembered about splice, so i guess i'm going to end up with: -- my @array=qw/zero one two three four five six seven eight nine ten/; my @indicesToDelete = (2,4,6,7); my $deviation = 0;

Re: How to delete multiple indices from array

On 04/12/2017 03:00 PM, David Emanuel da Costa Santiago wrote: Hello! What's the best way to delete multiple indices from an array? i'm doing: --- my @array=qw/zero one two three four five six seven eight nine ten/; my @indicesToDelete = (2,4,6,7); if you have the indexes to

How to delete multiple indices from array

Hello! What's the best way to delete multiple indices from an array? i'm doing: --- my @array=qw/zero one two three four five six seven eight nine ten/; my @indicesToDelete = (2,4,6,7); my %hash; @hash{(0..scalar(@array)-1)} = @array; delete $hash{$_} for @indicesToDelete;