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Topic: Automating an iterative procedure
Replies: 9   Last Post: Feb 25, 2013 3:39 AM

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dpb

Posts: 8,100
Registered: 6/7/07
Re: Automating an iterative procedure
Posted: Feb 23, 2013 4:47 PM
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On 2/23/2013 3:01 PM, Milos Milenkovic wrote:

...[top posting repaired--please don't: hard conversation follow makes]...

> dpb <none@non.net> wrote in message <kgb86j$446$1@speranza.aioe.org>...
>> On 2/23/2013 2:04 PM, Milos Milenkovic wrote:
>> ...

>> > K1=[-0.2582 -18.596 0 -0.2582;
>> > -34.737 -1300.188 0 -34.737;

>> ...
>> > for i=1:100
>> > B1(1)=[0.01 0.02 0.07 0.03;
>> > 0.02 0.05 0.06 0.02;
>> > 0.07 0.09 0.01 0.03;
>> > 0.01 0.03 0.02 0.04];

>>
>> ...
>>
>> No, but why would you want to duplicate a constant array anyway?
>> Sometimes for matrix operations there's a need/desire to do so, but
>> generally a temporary via repmat() or some other technique would be
>> more reasonable than just holding multiple copies of the same array.
>>
>> B1(1) refers to a single array location whereas the rhs is an array.
>> "Can't put 5-lbs of 'taters in a 1-lb tote" to use the E TN vernacular.
>>
>> Only a cell array element can hold another array.
>>


...

>> B1(1) and B0(1) are given matrices in iteration 1, then for the next 99
>> iterations I want to calculate updates of these matrices.


Oh.

Move the initiation outside the loop then store new values into the
desired location(s) in the array inside the iterative portion (the loop
iow). To do that you don't need to subscript B1 at all other than to
address individual elements therein if required. But, if you can
vectorize the computation of B1 then there's no need for the indexing.

Are you needing to save all iterations to the bitter end?

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