Re: How to vector

sub vector { my ($aa) = @_; $aa->[0] = my $one; $aa->[1] = my $two; $aa->[2] = my $three; my $vector = V($one, $two, $three); }
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In this function:

The function is passed an array reference;
The first three elements of the referent of this array reference are assigned the initial values (undef) of three newly-created lexical scalars;
The values (all still undef) of these newly-created scalars are passed to the Math::Vector::Real::V() function;
The return value of the V() call is assigned to a new lexical scalar $vector (which immediately goes out of scope) and is also implicitly returned from the function call.

Does passing the scalar values of $one $two $three (all undef) to V() serve any purpose? Given that its argument parameters are always the same, can V() ever return any differing value; i.e., is it an impure function?

I haven't examined Math::Vector::Real at all, but I would suspect things begin to go wrong within the vector() call itself.

Give a man a fish: <%-(-(-(-<

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Re^2: How to vector by jcklasseter (Sexton) on Jun 19, 2015 at 20:35 UTC
Well, I was trying to have field 0,1,and 2 assigned to one, two, and three. Then have the vector assigned with this values as it's values. How could I change the array reference to each field value?	[reply]
Re^3: How to vector by AnomalousMonk (Archbishop) on Jun 19, 2015 at 21:03 UTC
How could I change the array reference to each field value? As I understand it, the array reference already references each field's value. You need to pass these values to `V()`. Maybe something like (untested): `sub vector { my ($aa) = @_; return V(@$aa); }` [download] Again, I haven't studied the relevant module. As you can see, most of the function defined above is irrelevant. Why not just (also untested): `my $some_scalar = V(@$original_array_reference);` [download] instead? Update: After actually looking at Math::Vector::Real, it seems that `V()` returns a blessed reference of some kind (update: you also ~~reference~~ \| make note of this below), not a floating point number as implied by the `%f` format specifier in the OPed `printf` statement. You will have to manipulate this `V` object into some form of data usable to you, which I cannot judge. Give a man a fish: `<%-(-(-(-<`	[reply] [d/l] [select]