I want to select a random value but previously selected value are excluded from the selection. How can make like this??

Tag: matlab

I want to select a random value but previously selected value are excluded from the selection. How can make like this??

This approach is generalized one.. `A`

could have any values, some numbers repeating or non repeating.. also any number of(of course upto `numel(A)`

) could be generated.

**Code:**

```
A = randi(50,3,3); %// replace this with your own matrix
idx = 1:numel(A); %// generating linear indices
noOfRandNos = 5; %// How many such numbers do you want?
randNos(noOfRandNos,1) = 0; %// pre Allocation
%// This loop is run as many times as the number of such numbers you require.
%// Maximum possible runs will be equal to the numel(A).
for ii = 1:noOfRandNos
randidx = randi(numel(idx)); %// generating a rand Indx within the current size of idx
randNos(ii) = A(idx(randidx)); %// Getting corresponding number in-turn from the indx
idx(randidx) = []; %// removing the particular indx so that it is not repeated
end
```

**Sample Run:**

```
>> A
A =
12 28 25
23 27 32
49 12 34
>> randNos
randNos =
28
49
34
12
32
```

Here's another indexing-based approach: n = 10; C = [A; B]; [~, ind] = sort([1:size(A,1) n*(1:size(B,1))+.5]); C = C(ind,:); ...

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Use w+ or r+ when using fopen, depending on what you want to do with the file and whethe you want to create it or simply open it. From (http://www.tutorialspoint.com/c_standard_library/c_function_fopen.htm) "r" Opens a file for reading. The file must exist. "w" Creates an empty file for writing. If a file...

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TL;DL: net.trainParam.max_fail = 8; I've used the example provided in the page you linked to get a working instance of nntraintool. When you open nntraintool.m you see a small piece of documentation that says (among else): % net.<a href="matlab:doc nnproperty.net_trainParam">trainParam</a>.<a href="matlab:doc nnparam.showWindow">showWindow</a> = false; This hinted that some properties are...

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You can extract the numerator and denominator with numden, then get their coefficiens with coeffs, normalize the polynomials, and divide again. [n,d] = numden(T); cn = coeffs(n); cd = coeffs(d); T = (n/cn(end))/(d/cd(end)); The output of latex(T) (note: no simplifyFraction now; it would undo things): Of course this isn't equal...

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You can use the bitdepth parameter to set that. imwrite(img,'myimg.png','bitdepth',16) Of course, not all image formats support all bitdepths, so make sure you are choosing the the right format for your data....

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arrays,matlab,math,for-loop,while-loop

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Unless you have some implementation bug (test your code with synthetic, well separated data), the problem might lay in the class imbalance. This can be solved by adjusting the missclassification cost (See this discussion in CV). I'd use the cost parameter of fitcsvm to increase the missclassification cost of the...

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M =[0 0 0 0 0 1 0 0 0 0 0 2 0 0 0 0 0 2 0 0 0 0 0 1 0 1 0 0 0 1 0 4 0 0 0 0 0 3 0 0 6 0 0 4 0 0 3 0 0...

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From the Matlab forums, the dir command output sorting is not specified, but it seems to be purely alphabetical order (with purely I mean that it does not take into account sorter filenames first). Therefore, you would have to manually sort the names. The following code is taken from this...

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If you simply want to ignore the columns/rows that lie outside full sub-blocks, you just subtract the width/height of the sub-block from the corresponding loop ranges: overlap = 4 blockWidth = 8; blockHeight = 8; count = 1; for i = 1:overlap:size(img,1) - blockHeight + 1 for j = 1:overlap:size(img,2)...

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