> Not being a PDL'er myself, but interested in learning more about it and
> making sure Perl 6 doesn't suck, I'd love to see a bulleted list of what
> doesn't work right, even assuming that @arrays were made more flexible.
> For example, if you could do this:
>
> @c = @a * @b;
> @c = @a + @b;
> @c = (@a - @b) * (@d / @e);
>
> What other specific problems remain? TIA.
I'm not a PDL'er myself, either. But I haven't noticed a syntax
suggested for multidimensional arrays that looks good to me yet.
How are they indexed? $matrix[$x][$y][$z] is (too me) too C'ish, and
implies that @matrix is implemented as an array of arrays of arrays,
instead of some more efficient, compact structure. $matrix[$x,$y,$z]
already has a reasonable meaning. If we appropriate that syntax, how
do you take slices of a matrix?
I'm thinking I like using ; as an index separator, as in
$matrix[$x;$y;$z]. This -shouldn't- be a massive problem for parsing;
we are already using ; in "for(;;)" as something other than a statement
separator.
This would also allow us to do slices like: @matrix[1,3,5;2,4,6;3] to
get a 3x3x1 resulting matrix consisting of $matrix[1;2;3],$matrix[1;4;3]
, etc.
How are literal multidimensional arrays written? For this, I'm not
sure... My first thought was to separate the rows with ;, as in
@matrix = ( 1,2;3,4). But that doesn't scale well to more than 2d.
Then I thought just using the standard list of list syntax: @matrix =
( [1,2],[3,4] ). But is that a list of array references, or a 2-d
array? Next, I thought of combining the two:
@matrix3x3x3 = ( [[ 1, 2, 3];
[ 4, 5, 6];
[ 7, 8, 9]]; # row 0;
[[10,11,12];
[13,14,15];
[16,17,18]]; # row 1;
[[19,20,21];
[22,23,24];
[25,26,27]] ); # row 2;
I think parenthesis might be better, using [] for reference
constructors, but any way you look at it.
Should explicit bounds and declarations take place before use? Is "my
@matrix:bounds(3,3,3);" necessary? I don't know about you, but
autovivication of array elements and boundlessness is a feature I like
about perl. Why should "$array[1000] = $x" work without predeclaration
but "$matrix[1000;1000;1000] = $x" shouldn't?
Just my thoughts?
>
> -Nate
--
Buddha Buck [EMAIL PROTECTED]
"Just as the strength of the Internet is chaos, so the strength of our
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