MATLAB: How to find maximum without duplicates

duplicateindicesMATLABmaxtie

I have the matrix, A = [1 2 1 0 0 2; 2 1 4 2 0 0; 1 1 0 2 1 1; 1 1 0 1 4 2] I understand that max(A) gives the maximum for each column,but how do I create a logical array locating the maximum of each column? If there is a tie, I just want to consider the first occurrence of the maximum.

Best Answer

A        = [1 2 1 0 0 2; 2 1 4 2 0 0; 1 1 0 2 1 1; 1 1 0 1 4 2];
[v, ind] = max(A, [], 1);

Now ind is the row index of the first maximum value per column.

And a "logical array locating the maximum of each column":

siz = size(A);
L   = false(siz);
L(sub2ind(siz, ind, 1:siz(2))) = true;

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MATLAB: How can a phrase the constraint for Genetic Algorithms to generate data without duplicates

Hi,

As far as I understand, there is no direct option to remove duplication of data points in Genetic Algorithm. However, as a workaround, you could consider one of the two approaches listed below:

The best option is to create an initial population by writing your own creation function without duplicate points.
The second option is to cache/store the population. You can implement a simple strategy to create a cache inside the fitness function which can store the population evaluated in the past few generations. The size of the cache can be decided upfront so that it remains the same during the iterations. Using vectorized option will send all the population at once to the fitness function and that will be helpful.

If this does not address your query, you could consider contacting MathWorks Technical Support corresponding to the region you belong to using the following link:

http://www.mathworks.com/support/contact_us/

Regards,

Vidya

MATLAB: How to use Unique command to remove duplicates but still can use the data of the removed duplicates

Do not use globals to share data between callbacks. Use either the ApplicationData (e.g. as by guidata) or the 'UserData' of e.g. the figure.

[uC, iA, iC] = unique(compound);
handles.Compounds.iA    = iA;
handles.Compounds.iC    = iC;
handles.Compounds.Coeff = rand(1, numel(compound)); % ???
handles.Compounds.Name  = uC;  % Stored as 'String' also in the next line:
set(handles.popupmenu1, 'String', uC);
...
guidata(FigureHandle, handles);  % Update the handles struct

Then in the callback:

function popup1Callback(PopMenu1H, EventData)
handles = guidata(PopMenu1H);
index   = get(PopMenu1H, 'value');
string  = handles.Compounds.Name{index}
origIndex = handles.Compounds.iC(handles.Compounds.iA(index));
origMatch = (handles.Compounds.iC == origIndex);
origCoeff = handles.Compounds.Coeff(origMatch)

Best Answer

Related Solutions

MATLAB: How can a phrase the constraint for Genetic Algorithms to generate data without duplicates

MATLAB: How to use Unique command to remove duplicates but still can use the data of the removed duplicates

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