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# Ridwan Alam

##### Last seen: 4 days ago
127 total contributions since 2019

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find a set of data in an array
idx = find(A~=0); B = A(idx); idx and B have the same size and order. I believe this is what you are looking for?

20 days ago | 0

How can I select rows in an array based on the values in the first column of another array?
new_array = second_array(first_array,:)

21 days ago | 1

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adding different number of columns to specific row
Try using the table join() method: https://www.mathworks.com/help/matlab/ref/table.join.html Example: M_obs = readtable('book...

21 days ago | 0

How to display all values of an iteration?
for i = 1:100 xc = (x1 + x2)/2; if f(x1)*f(xc)<0 x2 = xc; else x1 = xc; end disp(['x1...

21 days ago | 0

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How to replace a rectangle with another rectangle?
I tried this, it worked for me: r = rectangle('FaceColor', [0.2 0.2 0.7]); r.FaceColor = [0.2 0.2 0.2];

21 days ago | 0

Changing array size of user input data
myCell = {}; k = 0; for i = 1:5:number k = k + 1; myCell{k,1} = i:min(i+4,number); end writecell(myCell,fullfile(...

21 days ago | 0

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Problem with function handle for Basis function in fitrgp
load(fullfile(matlabroot,'examples','stats','gprdata2.mat')) In this case, your x is n x 1; hfcn returns H, which has size n ...

23 days ago | 0

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Errors using function and fsolve
% *Set universal constants:* global surr sink sigma sigma = 5.67e-8; % Stefan-Boltzmann constant (in W/m^2/K^4) % % *S...

27 days ago | 0

Linear regression outputs (regstat function)
The first one is for the constant coefficient (aka intercept term). I believe you have only one predictor x, then your model is...

27 days ago | 0

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T-wave on ECG
If I understood right what you are asking, you need to find the peaks for P,Q,R,S, and T using findpeaks(). https://www.mathwo...

1 month ago | 0

making dataset 3D data function
Let's assume your variables are named as 'input01', 'input02', ... 'input48'. my3Ddata = []; myMeanData = []; varnames = wh...

1 month ago | 0

How can I save a image from imshow into a cell array ?
I don't think you need the imshow(). imshow() is only used to show the image, and it returns an image object, which is not norma...

1 month ago | 0

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Piecewise function of y
It's a bit hard to understand the issue here. Please let me know if this is not what you are looking for: plot(C2(20:90), heigh...

1 month ago | 0

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Replacing NaN with blanks in a matrix
I believe you are looking for fillmissing() or rmmissing(): https://www.mathworks.com/help/matlab/ref/fillmissing.html https:/...

1 month ago | 0

linear regression of time series with time index
If you have a fixed equation like the one provided, I believe you are looking for parameter estimation methods to find beta_0, b...

1 month ago | 0

K = round(Tuq'*eye(5)*Tuq,2); M = [ m 0 0 ; 0 m 0 ; 0 0 I ]; eq = det(K*k-w1*M); s = solve(eq,w1); will prevent sym() to con...

2 months ago | 0

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FFT filter on voice file help please
There are multiple ways you can filter these data. You can use bandpass, high or low pass filters, or any other specific filters...

2 months ago | 0

Change the Samples per frame property on the Sine Wave block: https://www.mathworks.com/help/dsp/ug/transform-time-domain-d...

2 months ago | 0

Digital signal processing LINEAR AND CIRCULAR CONVOLUTION length-N sequences error
x = [2+3j 3-1j -1+2j 3j 2+4j]; https://www.mathworks.com/help/matlab/ref/j.html

2 months ago | 0

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How to detect variations in data?
Depends on how complex of a solution you are looking for. There are algorithms for change point detection that you can try. htt...

2 months ago | 1

Which Right Eigenvector to report?
I assume you meant 'right' as opposed to 'left' eigen vectors. [V,D] = eig(A); % to get left eigenvectors, [V,D,W] = eig(A), he...

2 months ago | 0

Creating a table for the "For-loop command" results:
Even though there are many more efficient ways to do this, this is a simple addition to your code: clear clc n=input('Enter t...

2 months ago | 0

How to extract sub-matrices from a big matrix?
% to find the matched date and store the that day along with the following 5 days (120 hours) in another matrix. for n = 1:siz...

2 months ago | 1

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How to change nonzero values to 1 within a table?
tempTable = table2array(myTable); tempTable(tempTable~=0)=1; myTable = array2table(tempTable);

2 months ago | 0

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Replace NaN's in a table - I need some help

2 months ago | 1

Adding values of Columns in a matrix to create another matrix (for loop)
dim=size(E_min,2); % dim = 25 fun = @(E) A*exp(-E/kT); Np = []; nyi = []; for i = 1:dim Np(i)=integral...

2 months ago | 1

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How to mark a specific point on CDF graph?
Assuming you have 4 cdf arrays, you can find the x-values as: cdf1ind = find(cdf1>=.80,1,'first'); x1 = x(cdf1ind); cdf2ind = ...

2 months ago | 0

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How to write a code to estimate parity of numbers in a sequence?
bnumbers = [5 0 8 3 9 2 7 6 1 4 8 1 0 5 9 7 2 6 3 4]'; bresponse = [0 0 1 0 0 0 0 0 0 2 0 2 2 0 0 0 0 0 0 0]'; bbinary = ...

2 months ago | 0

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Signal Decomposition for a mixed signal
t=0:0.00001:0.3; x1=(exp(-3*t)).*(0.2*sin(2*pi*400*t)); x2=1.2+(exp(-1.5*t)).*(1.1*sin(2*pi*40*t+pi/6)); x3=(exp(-5*t)).*(0.8...

2 months ago | 0

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