sage: u=vector([2+3*I,5+2*I,-3+I])
sage: v=vector([1+2*I,-4+5*I,0+5*I])
sage: p1=u*v;p1.expand()
9*I - 39
sage: p2=u.inner_product(v);p2.expand()
9*I - 39
sage: p3=u.dot_product(v);p3.expand()
9*I - 39
sage: p4=u.inner_product(vector([i.conjugate() for i in v]));p4.expand()
3 - 19*I


Am I right in the assumption that for the inner product of two complex
vectors, the result should be the sum of the element wise  multiplication of
the  element of the first vector times the complex conjugate of the element
of the second vector? I had to do this by hand, as you can see for p4. I had
a look at Mathematica, and it seems like they don't do it either. So I might
be wrong.

Another thing:

sage: parent(p1)
Symbolic Ring
sage: parent(u)
Vector space of dimension 3 over Symbolic Ring

is it meant to be over symbolic Ring?

and one more:

sage: k=vector([complex(1,2),complex(3,4),complex(25,15)])
Traceback (most recent call last):
...
TypeError: unable to find a common ring for all elements

seriously? why that?

sage: u=vector(CC,[complex(1,2),complex(3,4),complex(25,15)]);u
(1.00000000000000 + 2.00000000000000*I, 3.00000000000000 +
4.00000000000000*I, 25.0000000000000 + 15.0000000000000*I)

And now I've got creepy precision stuff in there. And the inner product
still doesn't do what I'd like it to.

Does a complex number from CC constructed by complex(<re>,<im>) have as
resulting real and imaginary part have elements from RR? What's the
difference between RR and QQ anyway? QQ is arbitrary precision, does RR use
machine precision maybe?

Now maybe I've asked too many questions, but I've had no luck with the
reference manual so far (maybe I just don't get the explanations in
there...).
I know that today there's the big AMS meeting (good luck for that), so no
need to hurry in order to reply for anyone. And excuse my English, there
maybe some mistakes since I'm in a rush...

Thanks a lot, Fabio

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