Assign column index to output value
An easier way to create the submatrix: submatrix = M(i:end, :); The any() operates along the first non-singelton dimension. Fo...

Index exceeds the number of array elements (4)
You stop Matlab at the error already by dbstop if error. Then use the debugger to check the sizes of the arrays: size(zplot) s...

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Problem with Matrix indexing using vector
This is a job for sub2ind: a = blkdiag(ones(3),ones(3)); [r,c] = find(a); b = zeros(size(a)); index = su...

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MEX passing Integer - wrong results
This sounds magic. Whenever magic things appear in discussions in the forum, or at programming in general, it is a secure signal...

how to avoid for loop
A ,ore efficient version of the loop: nb = numel(b) - 1; counts = zeros(1, nb); % Pre-allocation!!! for i = 1:nb co...

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Using matlab to find vectors that are orthogonal to another vector.
Do you mean 2D vectors? v = rand(1, 2) % Any test vector vp = [-v(2), v(1)] dot(v, vp) % Orthogonal means: dot pro...

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11221 212211 212 12 1
Please post an exact copy of the error message in the forum. A rough paraphrasing will hide important details. Thanks. I assume...

faster way to add many large matrix in matlab
The main time is spent in rand() in your example. With using ones() instead, the runtime goes from 0.71 sec to 0.25 sec on my ma...

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Convert CurrentPoint to X and Y Value.
I guess that you do not want the coordinates relative to the figure, but relative to the data in an AXES object. Then: CP = get...

P files cannot be analyzed to find their dependencies. Please add P file dependencies manually
I'd start with a web search: Ask your favorite search engine for "Matlab get dependencies of P file". You will find e.g.: https...

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Is it possible to concatenate structures with the same fields in to one super structure?
Or with a loop: function S = CatStructFields(S, T, dim) fields = fieldnames(S); for k = 1:numel(fields) aField = field...

Query in applying If command
if (abs(G(j)-O(:))<1) The if command needs a scalar condition. Therefore Matlab inserts an all() to evaluate the vector G(j)-O(...

Index in position 1 exceeds array bounds (must not exceed 5).
The variable tab has the dimensions 5 x 10. You try to access the indices [100, 5, 10]. This cannot work. I guess, you want to r...

How to Assign vectors to each dynamic variable name?
Don't do this. See: TUTORIAL: How and why to avoid Eval Hiding an index in the name of variables is a bad idea. Use arrays ins...

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Can I construct a matrix multiplying a scalar and a vector?
No, tis is not a standard multiplication. But you can create k based on i and j: i = 3; j = [4; 5]; % Solution 1: k(:, 2) ...

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How can I maximize a function in Matlab?
Matlab contains some tools for minimization. A maximization does exactlly the same, if you change the sign of the optimization c...

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How do I access a certain directory?
You can define the path of a file to access it: Folder = 'C:\Temp\'; FileList = dir(fullfile(Folder, '*.jpg')); for iFile = 1...

i wanted the slope with respect to time frame
Maybe all you need is to call the gradient(X.') function, where X is the complete matrix?

Efficient way to rename files adding prefix from higher rank folder
% Assuming that the Subject_folder's are contained in D:\Your\Folder\ : BasePath = 'D:\Your\Folder\'; BaseLen = length(BasePa...

Save figure as jpg with 600dpi
saveas('figure.jpg') The first input must be the handle of a figure. print(gcf, 'figure.jpg', '-jpg', '-r600'); There is no '...

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i am not able to debug because my window is not showing the debug points
Did you try to create the debug points by clicking in the area behind the line numbers? The file has not been saved. So save it...

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How to shorten space between space in command window
Avoid the \t for formatting the output if you want to get nice ASCII tables. Prefer to define the width: fprintf('%s%10d%10d%10...

If else Statement in GUI
I guess, that Matlab does exactly what it is expected to do. If h(a)*h(b)>0 is false, Matlab enters the else branch. Although y...

how to resolve this "not enough input arguments" from the code shown below
objFun=@(mag)summ Now calling objFun calls summ without input arguments. I assume, you mean: objFun = @summ which is a more e...

Create a for cycle over an array
Do not create a bunch of variables with an index hidden in the names: See TUTORIAL: Why and how to avoid Eval I assume all you ...

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why do i get Nan as output?
Use te debugger to determine the first occurrence of a NaN. Type this in the command window: dbstop if naninf Then run the cod...

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Why is vectorization faster than the parallel computing？
It depends on the problem. Parallelization is not trivial. If you use e.g. 16 cores and write the results in neighboring element...

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How it works : Bilinear interpolation for image resizing
According the the documentation: "the output pixel value is a weighted average of pixels in the nearest 2-by-2 neighborhood" T...

Workaround for matrix dimension error
Hints: Avoid repeated code. Prefer: brtn = 255 * get(handles.slider1, 'Value'); instead of writing 255*brtn whenever brtn is ...