some clarifications below

On 08/21/2013 05:19 AM, Doug McNutt wrote:
>> ***** a "function" is a subroutine returning a scalar  ( see below)

fwiw we don't make that distinction in the specification; we just talk
about subroutines. We can return nothing, a scalar or a non-scalar.

>>, a "procedure" is a subroutine with no
>>return value, side-effects only. A subroutine returning many values- a
>>parcel of containers, perhaps, or an iterator, etc- is a
>>"many-to-many" relation. I understand "relational algebra" from
>>decades of SQL work, and have seen ORM's replicate relations in object
>>systems with some success. What's missing for creating a relational
>>wonderland in perl6?
> I confess.  I'm here because I hoped perl 6 would do vector operations after 
> reading an early small book.

And it does, if you teach it to.
Perl 6 has some facilities to spread out operations over lists of
elements, though not all operations common in linear algebra (vector
cross product, multiplying a vector with a matrix etc.) are built-in.
Just like they aren't built into Fortran, for that matter.

> I would really like to see perl support a function called a cross product 
> that would return a vector, the product of amplitudes and the sine of the 
> angle between them, as a vector using the <>  notation.  That's not a scalar! 
>  But i surely would be commensurate with the input arguments.

Please don't fall prey to some mismatch in terminology. In Perl 6, a
scalar is just some form of container, which happens to be used in
variables beginning with a dollar ($). Nothing stops you from putting a
vector, however you define or declare one, into a scalar (variable). Nor
is there any restriction that makes it impossible to return more than
one value from a subroutine -- it just happens to be the case that
yary's definition of "function" restricts functions to one value. But
that's really a matter of terminology, not technology.


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