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From: Xavier Ho <contact@xavierho.com>
Date: Thu, 11 Apr 2013 09:27:08 +1000
Subject: Re: Functional vs. Object oriented API
To: Max Bucknell <mpwb500@york.ac.uk>
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Hi Max,

In Python, we prefer readability over anything else.  The simpler you can
write it, the better it can be understood.

That said, I've never considered using (i, j, k) as a vector component
before.  I've always done something akin to:

>>> vector = Vector(2, 4, 6)
>>> print (vector.normalize().y)

However, if you use the mathematical definition of a vector, with standard
symbols:

    v = x*i + y*j + z*k

Then I believe vector.j is a much choice.  As long as your documentation
states it's read-only, I think most mathematicians will love that notation.

.

As far as dot products go, there isn't really a big difference between the
two forms you have there.  Both are equally as readable.

When C++ was invented people had already debated about the two forms.
 There isn't a general consensus on this debate, but most would probably
agree that overloading the * operator of a vector to do dot product is a
bad idea, since some people want cross product, or per-component
multiplication.  At the end of the day, dot() or dot_product() is more
readable, and it doesn't matter if you have it as a function in or outside
of a vector's class.

Cheers,
Xav

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<div dir=3D"ltr">Hi Max,<div><br></div><div>In Python, we prefer readabilit=
y over anything else. =C2=A0The simpler you can write it, the better it can=
 be understood.</div><div><br></div><div>That said, I&#39;ve never consider=
ed using (i, j, k) as a vector component before. =C2=A0I&#39;ve always done=
 something akin to:</div>

<div><br></div><div>&gt;&gt;&gt; vector =3D Vector(2, 4, 6)</div><div>&gt;&=
gt;&gt; print (vector.normalize().y)</div><div><br></div><div style>However=
, if you use the mathematical definition of a vector, with standard symbols=
:</div>

<div style><br></div><div style>=C2=A0 =C2=A0 v =3D x*i + y*j + z*k</div><d=
iv style><br></div><div style>Then I believe vector.j is a much choice. =C2=
=A0As long as your documentation states it&#39;s read-only, I think most ma=
thematicians will love that notation.</div>

<div style><br></div><div style>.</div><div style><br></div><div style>As f=
ar as dot products go, there isn&#39;t really a big difference between the =
two forms you have there. =C2=A0Both are equally as readable.</div><div sty=
le>

<br></div><div style>When C++ was invented people had already debated about=
 the two forms. =C2=A0There isn&#39;t a general consensus on this debate, b=
ut most would probably agree that overloading the * operator of a vector to=
 do dot product is a bad idea, since some people want cross product, or per=
-component multiplication. =C2=A0At the end of the day, dot() or dot_produc=
t() is more readable, and it doesn&#39;t matter if you have it as a functio=
n in or outside of a vector&#39;s class.</div>

<div style><br></div><div style>Cheers,</div><div style>Xav</div></div>

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