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Topic: Insert row in an array and delete last row
Replies: 7   Last Post: Jan 21, 2013 2:38 AM

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 dpb Posts: 9,839 Registered: 6/7/07
Re: Insert row in an array and delete last row
Posted: Jan 20, 2013 2:17 PM

On 1/20/2013 11:11 AM, Michael Doukas wrote:
> "Michael Doukas" wrote in message
> <kdh748\$a5g\$1@newscl01ah.mathworks.com>...

>> I have the following code (it is for a Tabu search algorithm):
>>
>> 1: InitialSol=generator;

2: lsol=size(InitialSol,2);
>> 3: List=zeros(l,lsol);
>> 4: i=0;
>> 5:

6: while i<=l
>> 8: Sol=tweak(InitialSol);
>> 9: % check if tweaked child already exists in the tabu list
>> 10: if ismember(Sol,List)==0
>> 12: List=circshift(List,1);

13: List(i,:)=Sol;
>> 14: i=i+1;
>> 15: end
>> 16: end
>> But it reaches line 13 and throws:
>> Subscript indices must either be real positive integers or logicals.

...

Quite a few problems here...

The immediate problem is that you initialized i to zero and so the first
time there's a new entry added the subscript for L(i,:) is L(0,:).

Either initialize i=1; or move the increment to be before the first usage.

But, the ismember() usage isn't right, anyway...remember the 'rows'
optional argument? Plus, it returns a logical array which will be T iff
each member is T. If the idea is to not have any duplicates in L, then

if ~any(ismember(Sol,List,'rows')

doc any
doc equal

--

Date Subject Author
1/20/13 Michael Doukas
1/20/13 dpb
1/20/13 Michael Doukas
1/20/13 dpb
1/20/13 Michael Doukas
1/20/13 Michael Doukas
1/20/13 dpb
1/21/13 Michael Doukas