Re: Arrays ... need clarification....

Thank you for the feedback.

It would be great to see what is in cvs now make it into 7.4 .

Joe Conway wrote:

> Guy Fraser wrote:
>
>> Is there a psudo data type that can be used as a function input type
>> for any kind of array?
>
>
> Not really in 7.3.x, but it works in cvs now.

I had noticed the anyarray somewhere before but I don't think I was able
to use it [IIRC].

>
>> I have built some functions that take dims output and return an
>> integer value {n, where bounds are from 1 to n} of elements in an
>> integer array and a text array but if I could make one function that
>> handles any type of array, that would be great.
>
>
> Also in cvs is array_lower(array anyarray, dim int) and
> array_upper(array anyarray, dim int), which will give you the '1' and
> the 'n' respectively.
>
>> Since you said you are improving the array features, could you make a
>> function like dims, that outputs the bounds as a 2D array integers of
>> integer sets?
>> ie. {{1,3},{1,4}} rather than [1:3][1:4].
>
>
> Same functions mentioned above:

...snip...

>
> But I guess returning all the array bounds as an array might be a nice
> function to have too.
>
>> Some of the other things I would like to see is :
>> - the ability to populate an array from a set of data rows
>
>
> This works in cvs also:
>
> CREATE TEMP TABLE arrtest_f (f0 int, f1 text, f2 float8);
> insert into arrtest_f values(1,'cat1',1.21);
> insert into arrtest_f values(2,'cat1',1.24);
> insert into arrtest_f values(3,'cat1',1.18);
> insert into arrtest_f values(4,'cat1',1.26);
> insert into arrtest_f values(5,'cat1',1.15);
> insert into arrtest_f values(6,'cat2',1.15);
> insert into arrtest_f values(7,'cat2',1.26);
> insert into arrtest_f values(8,'cat2',1.32);
> insert into arrtest_f values(9,'cat2',1.30);
> regression=# SELECT ARRAY(select f2 from arrtest_f order by f2) AS
> "ARRAY";
> ARRAY
> -----------------------------------------------
> {1.15,1.15,1.18,1.21,1.24,1.26,1.26,1.3,1.32}
> (1 row)

...snip...

>
>> From these features alone, many new array functions could be
>> possible using other standard features.
>>
>> Most of the arrays I deal with are text arrays, so the PL/R and
>> int_array stuff doesn't help me.
>
>
> You can certainly pass text arrays to PL/R, and R is inherently a
> vector (array) processing language. You obviously wouldn't need all
> the statistical processing power of R, but I think you'd find it makes
> most manipulations or arrays fairly easy.
>
> Joe

Guy