In article <2ecbd17e-24b0-427a-ad81-28b05641463dn@googlegroups.com>,
Laurent MANCHON <manchon.lm@gmail.com> wrote:
>--
>Sure Tawk can do that ?
>--

yes.

--
To most Christians, the Bible is like a software license. Nobody
actually reads it. They just scroll to the bottom and click "I agree."

- author unknown -

--
i confirm, it works i have changed array[i,j] to array[i][j]
and the concatenation step to:

list[i]=list[i] SUBSEP array[i][j];

In article <24b17405-ad5d-46e9-8d07-46917097b34cn@googlegroups.com>,
Laurent MANCHON <manchon.lm@gmail.com> wrote:
>--
>i confirm, it works i have changed array[i,j] to array[i][j]
>and the concatenation step to:
>
> list[i]=list[i] SUBSEP array[i][j];
>

And then what?

I don't know if you've ever really explained what it is you're doing, but
let me just say that whever I see "SUBSEP" in user code, I assume that the
programmer is trying to create a subscript in a pseudo-multi-dimensional
array. If that is the case for you and your code, then I'd argue that you
shouldn't be doing that, since you could be using real-multi-dimensional
arrays instead.

However, sometimes programmers use SUBSEP as a quick-and-dirty separator
for data, arguing that it is more or less guaranteed to never occur in
data, having nothing to do with pseudo-multi-dimensional arrays. This
usually works but is confusing to the reader of the code, since it looks
like array stuff.

Personally, I usually end up using ^A when I need a fake data separator.

Is there any particular reason why you are using SUBSEP in the code above?

--
Mike Huckabee has yet to consciously uncouple from Josh Duggar.

--
absolutely, I use SUBSEP as a concatenation separator.
I could have declared SUBSEP=";" in the begin statement for more security.

On 8/12/2021 7:13 AM, Laurent MANCHON wrote:

[When posting please include enough context that your post makes sense
stand-alone - this is usenet, not a forum]

> --
> i don't work with very long lines, but i work with very big text files with million of rows.
> In in my opinion the main drawback of all awk's family is the string concatenation, it takes too much time,
> and this is what I have noted.
> Maybe it's common to all languages, I don't know how C handles it.
>
>

C handles it by requiring you to allocate enough memory up front when
you declare your variables for the maximum that might be required for
that variable. So in C you do something like (pseudo-code):

char x[50] # allocate 50 chars space in memory for x.
x = "foo" # the first 3 chars of x are populated with "foo".
x = x "bar" # the first 6 chars of x are populated with "foobar".

since x already has enough memory to add "bar" to the end but you don't
declare variables in awk so the equivalent is:

x = "foo" # allocate 3 chars space in memory for x and
# populate it with "foo".
x = x "bar" # allocate 6 chars space in memory for x, populate it
# with "foobar", and change the reference for "x" to
# point to the new memory location if required.

It's probably not exactly that simple and I'm sure gawk at least has
some optimizations for it but that gives you idea of why awk has more
work to do than C when concatenating a string to an existing variable -
static memory allocation for it in C vs dynamic memory allocation in awk.

Ed.

On 8/12/2021 2:01 PM, Laurent MANCHON wrote:
> --
> absolutely, I use SUBSEP as a concatenation separator.
> I could have declared SUBSEP=";" in the begin statement for more security.
>

Please include enough context in your posts so those of us trying to
follow them on usenet know what they're about. See the posts from
everyone else in this thread for examples of that.

Ed.

i think i understood.
in C you have to anticipate the size of the memory you will need. You don't know in advance how many concatenations you have to do.