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Re: An easier functional way to divide each Column of matrix by a

  • To: mathgroup at smc.vnet.net
  • Subject: [mg127160] Re: An easier functional way to divide each Column of matrix by a
  • From: Andre Koppel <akoppel at akso.de>
  • Date: Mon, 2 Jul 2012 22:20:09 -0400 (EDT)
  • Delivered-to: l-mathgroup@mail-archive0.wolfram.com
  • References: <jsrpt4$d52$1@smc.vnet.net>

Am 02.07.2012 11:33, schrieb Bill Rowe:
> On 7/1/12 at 2:05 AM, nma at 12000.org (Nasser M. Abbasi) wrote:
>
>> I think Mathematica is definitely biased towards rows. I think the
>> original designers of Mathematica liked rows much more than columns
>> :)
>
> Mathematica is definitely biased towards rows due to the rather
> fundamental usage of List. That is, a matrix is a list of rows
> not a list of columns. And it is this distinction that creates
> the bias for rows.
>
>
this seems to be similiar on every computersystem and language that I know:
In C you will write vektor[rows] and Matrix[rows][Columns]
This means every row contains all columns within this row.
On a display (either alphanumeric or graphical) it's the same, every row
contains all columns of this row. This means the Index most of the right
is the fastest counting one. Possibly you may address the first one of 
the second row by addressing the last one + 1 of the first row.
For me this is straight foreward. A row contains a list of all columns.
so a vektor is a list of rows (even if it's a horizontal vektor) and a 
row is a list of columns. For any kind of square matrices the complete
map may be flattened and back again reordered.
If you take a look in the HP 85 Matrix-Manual (written in the late 
80ies) there are several MAT-functions that do the same.
So I think ordering the things this way is "the natural way" :-)





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