[Jprogramming] Length of a vector

[Raul Miller]

I think what you are talking about here is a concept of context:

We can think of 1j2 as a vector. We can also anchor that vector at the
origin and think of it as denoting a position. We can think of the
difference between two positions as a vector.

Adding more dimensions means we cannot use a single complex value to
represent the vector, but more general concepts still hold.

Anyways, euclidean norm can find the length of two independent vectors
or, if we treat both as positions we can use euclidean norm on a
vector which is the difference of the other two, yes?

Or am I overlooking a key issue (again)?

Thanks,

-- 
Raul

On Tue, Dec 17, 2013 at 9:52 PM, Don Kelly <dhky at shaw.ca> wrote:
> I have some problem here with the 2D complex vector.
> Either 1j2 and 4j10 are vectors (2D) measured from the origin OR they
> specify a vector in terms of  two end points.
> In the first case they each have independent norms  1.414 and 2.236  as
> given by (|)
> In the second case the vector is,for example, the difference (+/-) 3j8which
> has a norm 8.544
> when en produces the same result for a 4D vector 1 2 4 10 and for 2 2D
> vectors, we are somehow sending one of these into the third and fourth
> dimensions.
>
> My problem is that a norm is defined for each of the vectors and or the
> vector result of operations on these vectors.   en appears to be work for a
> single vector in any dimensional space but the Euclidean norm is a measure
> of the length of an individual vector- not of two independent vectors in the
> same space.
>
> Don Kelly
>
>
> On 16/12/2013 7:24 AM, Bo Jacoby wrote:
>>
>> NB. I would omit ("1) and arrange multiple vectors in columns.
>>       en =: [: %: [: +/(* +)
>>       ]zz =: |: 2 2 $ 1j1 1j1 1j2 4j10 NB. two column vectors
>> 1j1  1j2
>> 1j1 4j10
>>     en 1 2 4 10 NB. norm of 4D real vector
>> 11
>>     en 1j2 4j10 NB. 2D complex vector
>> 11
>>     en zz  NB. norms of column vectors
>> 2 11
>>
>>
>>
>>
>>
>>
>> Den 15:42 mandag den 16. december 2013 skrev Lippu Esa
>> <Esa.Lippu at varma.fi>:
>>   Very nice indeed!
>>>
>>> Esa
>>> -----Original Message-----
>>> From: programming-bounces at forums.jsoftware.com
>>> [mailto:programming-bounces at forums.jsoftware.com] On Behalf Of Aai
>>> Sent: 16. joulukuuta 2013 14:42
>>> To: programming at jsoftware.com
>>> Subject: Re: [Jprogramming] Length of a vector
>>>
>>>      |@j./"1 yy
>>>    5 13
>>> 17 25
>>>
>>>
>>> On 16-12-13 04:38, km wrote:
>>>>
>>>> This is an easy one, but let's see what you come up with.
>>>>
>>>> The Euclidian norm or length of a vector is the square root of the sum
>>>> of the squares of its components.  Write verb  en  below.  It should be able
>>>> to find the length of a vector of any number of components.
>>>>
>>>>       ]yy =: 2 2 2 $ 3 4 5 12 8 15 7 24
>>>> 3  4
>>>> 5 12
>>>>
>>>> 8 15
>>>> 7 24
>>>>       en yy  NB. lengths of 3 4 and 5 12 and 8 15 and 7 24
>>>>     5 13
>>>> 17 25
>>>>
>>>> -- Kip Murray
>>>>
>>>> Sent from my iPad
>>>> ----------------------------------------------------------------------
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>>>
>>> --
>>> Met vriendelijke groet,
>>> @@i = Arie Groeneveld
>>>
>>>
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