How to extract coordinates from the pattern
white = 1; % or 255, depending on the format of your image [cy, cx] = ind2sub(size(I), find(I==1));

7 years ago | 0

Plotting bar graph using loop
A=xlsread(filename); for i = 1:3, h = histogram(A(:,i+1), [0 0.3 0.5 Inf]); hi(i,:) = h.Values; end bar(hi) legend({'0:0....

7 years ago | 0

three types of correlation coefficients for an image
I = im2double(imread('cameraman.tif')); c_diag = corrcoef(I(1:end-1, 1:end-1), I(2:end, 2:end)) c_vert = corrcoef(I(1:end-1...

7 years ago | 0

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Why is my Plot Blank?
You don't need the for loop, you can work on the vector beta. You just have to replace * and / with .* and ./ (you already use ....

7 years ago | 0

Finding a chain in an adjacency matrix
You can use the power of the adjacency matrix as detailed in <http://math.stackexchange.com/questions/222429/graph-theory-sh...

7 years ago | 0

want to make a number of row matrix from a single row matrix
Your description is somewhat unclear to me. Do you mean cat(3, reshape(line1, [3 3])', reshape(line2, [3 3])')

7 years ago | 0

line profile adding certain rows together
ind = [-3 -2 2 3] + rMiddle; % rows +/- 3 pixels from rMiddle, but without row rMiddle and the direct rows +/- 1 pixels ab...

7 years ago | 0

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How to select two matrices randomly from a set of N matrices and then randomly select a few rows from first selected matrix and then exchange with corresponding rows of other selected matrix.
Q = cat(3,A,B,C,D,E,F,G,H,I,J); kk = randperm(size(Q, 3), 2); % select 2 matrices from Q ii = randperm(size(Q, 1), 2); %...

7 years ago | 1

row-column confusion with squeeze
Squeeze squeezes out all singleton dimensions of X, *if X is not a matrix*. In case of C = squeeze(zeros(1,3,1)) who...

7 years ago | 1

How to find unique elements in a vector without using unique or find?
You can do this with for and if: suppose you have the numbers in x and want to generate the unique numbers in xu ...

7 years ago | 0

Merge a piecewise, parameterized Function
You can use logical indexing x = 1:100; y = [sin(x(x <= 20)) cos(x(x>20 & x <= 40)) tan(x(x>40))];

7 years ago | 0

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Undefined function 'x0' for input arguments of type 'double'.??
You try to evaluate x0(4*n) and it seems that x0 is not defined. It could be a variable, if 4*n is an index, or a functi...

7 years ago | 0

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Only the last user input is being stored, the rest are being replaced by zeros in my array.
Move the fprintf(fid1, '%6.3f,',n,y,x,z); inside the for loop.

7 years ago | 0

combining planes of data
M = cat(3, plane1, plane2, plane3,[more planes], plane512);

7 years ago | 1

Simple way to wrap quotes around input
str = ['''' str ''''];

7 years ago | 1

How to mirror matrix on the diagonal?
I2 = rot90(fliplr(I),-1);

7 years ago | 4

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I have a problem with a plot
plot(x, y1); hold on plot(x, y2) or plot(x, y1, x, y2)

7 years ago | 1

Low computation efficiency of simple sentence in MATLAB
Instead of X = repmat(lambda_old1,1,4).*[W1(:,i),W3(:,i),W2(:,i),W4(:,i)]; if might be faster to use X = bsxfun(@time...

7 years ago | 1

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How can I correct inhomogeneous intensity in image?
I = im2double(imread('blob.bmp')); y = mean(I(:, 1:100), 2); sigma = 30; % choosen by visual inspection G = f...

7 years ago | 0

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How can I solve the " Index exceeds matrix dimensions" error for the following code ?
Don't use negative indices like -2, they are always invalid. Valid indices in Matlab start with 1 and end with the number of ele...

7 years ago | 0

First check if the encoding is ISO-8859-1, such that accents are read correctly: if ~strcmp(feature('DefaultCharacterSet'), ...

7 years ago | 0

Randomize three chosen arrays in matlab
A = [0,0,1]; B=[0,1,0]; C=[1,0,0]; X = [A; B; C]; x = X(sub2ind(size(X), 1:3, randi(3, [1, 3])))

7 years ago | 0

concatenate all value in a matrix into one number
This works even if the numbers are not single digits, i.e., in in {1,2,...,9} v = [10 20 4]; num = sscanf(sprintf('%d', v...

7 years ago | 0

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Connecting line between different points obtained from a for-loop
x = 1:20; y = x+2; plot(x,y,'*-')

7 years ago | 0

Matlab delete's value's from array
You remove all rows that contain a NaN in the line k(any(isnan(k),2),:)=[]; and then you assign the variables varia...

7 years ago | 0

how can i find the displacement in pixels for the 1st, 3rd and 5th squares in the picture
% number here found by visual inspection I = im2double(imread('1.JPG')); index_center = size(I,2)/2+100:size(I,2...

7 years ago | 1

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Change the default filling of a matrix
I do not know anyway to change the default behaviour of Matlab to fill the empty positions with zeros. So you have to do it in t...

7 years ago | 0

Trying to make a "snake" matrix?
N = 5; M = 9; T = reshape(1:M*N, [M, N])'; T(2:2:end,:) = fliplr(T(2:2:end,:));

7 years ago | 0

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