Community Profile # Chunru

Last seen: Today Active since 2013

Matlab user since 1990

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Why the following code does not give me the 3D plot. Please someone help me out.
In your definition of R0, there is a term rho1+rho2, which happen to be 0. So R0 is just 0. Check your formula first.

etwa 11 Stunden ago | 0

How to find standard deviation of all entries in a range and omit nan
A=rand(10); StdssA=std(A(2:4,3:7), 0, 'all', 'omitnan') % doc std

etwa 19 Stunden ago | 0

How to reduce computation time with 8 nested for loop
Brute force searching for such problem is not feasible. If it takes around 10 days to reach to 10^13, it takes 10*10^11=10^12 d...

ein Tag ago | 0

Display value of a variable within ' '
system([stata_location ' -b do mydir/mydofile ' num2str(run_id)]);

ein Tag ago | 0

why is this happening? It's just an example from the textbook.
syms x f=@(x) x-3; r=solve(f, x)

3 Tage ago | 0

How to computer a frequency spectrum and find its largest spectral energy
fs = 10; tspan = [0:1/fs:100]; % specify the time points xint = [3.0;2.0;1.0]; [t,x]= ode45(@nonlin,tspan,xint); % remov...

3 Tage ago | 0

How to delete specific cells according to the condition from cell array?
If you want to keep the output as a cell array (as the input), you cannot delete them, but you can assign them to empty array. ...

3 Tage ago | 0

Finding the required number of high frequency values from histogram
a = [randn(10000,1)-5; randn(10000,1); randn(10000,1)+5]; histogram(a) [y,edges] = histcounts(a); % Use the center of edges...

3 Tage ago | 1

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How to find out roll-off from magnitude response of filter in matlab
fs = 2000; [b,a] = butter(9,400/(fs/2)); [h, f] = freqz(b,a,16384,fs); h = 20*log10(abs(h)); [~, i3db] = min(abs(h - 10*log1...

4 Tage ago | 0

Finding location of specific element from a MATRIX returns '0×1 empty double column vector'
[i,j] = find(abs(a-23.5975)<1e-20)

4 Tage ago | 0

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How to move a signal to be on the x-axis
try "detrend".

4 Tage ago | 0

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String to number from array
You can use "readmatrix" function: % Generate the data file a = [290729 123456 13984 654321 13272 111111]; writem...

4 Tage ago | 2

How to efficiently compare large multi-dimensional arrays together of different dimensions?
M = 512; N = 512; O = 136; P = 6; % Generate random matrix A = rand(M, N, O, P); thres = rand(O, P); % Thresh...

4 Tage ago | 0

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cross-correlation between a vector and and rows of a matrix
x = randn(40, 5); % better to make it column dominant order for speed y = circshift(x(:,1), 5); for i=1:size(x, 2) ...

4 Tage ago | 0

Should the filter frequency response contain magnitude greater than 3dB in magnitude?
if you have 10^-6 dB or lower, then the response is almost flat in amplitude. The design or something else is most likely wrong...

4 Tage ago | 0

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Plotting Response of Discrete Signals

5 Tage ago | 0

Error while plotting the polar plot
e = 0.5; thet = -60:1:60; theta = thet .*(pi/180); c = cos(theta); p = 4*(1-e^2).*(c.^2) + (2*e - 1)^2; % q = 2*(1-e*e).*...

5 Tage ago | 0

Plotting a Response of the Following system
% 𝑦[𝑛] = −𝑦[𝑛 − 1] + 5𝑥[𝑛] + 2𝑥[𝑛 − 3]. b = [5 0 0 2]; % 5x(n), 2x(n-3) a = [1 1]; % y(n) + y(n-1) % From an ...

5 Tage ago | 1

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How do I refer to values that contain decimal points and integers (for example, 1.0000 ... and 1)?
a = b(cellfun(@(x) abs(x -1 ) <1e-10, b(:,1)),:);

5 Tage ago | 0

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Question about how to put several values in one histogram
You should not use histogram. You should use bar: bar([3 4 3]) set(gca, 'XTickLabel', ["Player" "Computer" "Draw"])

5 Tage ago | 0

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How to find rest of the number in matrix ?
a = 1:10; I = find(a>5) aa = a(I) bb = a; bb(I)=[]; bb

5 Tage ago | 1

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who to write this function in another way?
fcn(-5) fcn(.34) fcn(4) function y = fcn(u) x0 = [-inf -0.9 -0.8 -0.6 -0.4 -0.2 0.2 0.4 0.6 0.8 0.9 1.5]; y...

5 Tage ago | 0

Comparing elements of two uneven lists of numbers
a1=[ 15 420 5778 6018 6388 ]; a2 = [ 414 1430 5762 6384 ...

6 Tage ago | 1

How to check a matrix is multibanded?
% Create a banded sparse matrix B = bucky; r = symrcm(B) a=B(r,r); imagesc(a); % Check if it is banded m = size(a,1); ...

6 Tage ago | 0

How to get the aircraft location from a flight path plot?
% Generate some data t = (7020:210:10080)'; lon = 102.915 - t/10080; lat = 1.363 - t/20000; heading = 153 + t/50040; % Cr...

6 Tage ago | 1

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How do I use a user input string to reference a structure that already exists?
Here is one solution without dynamically naming a variable: ... UserInput='ExistingStructure'; if exist(userInput, 'var') ...

9 Tage ago | 0

Group values of a vector into new vectors according to magnitude
A = [17 323 100 3 278 220 45 351 212 51] B = A(A>=0 & A<50) C= A(A>=50 & A<100) % Leave D for you

9 Tage ago | 0

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generating random numbers only 2 numbers
a = randi([0 1], [1 30])*3 + 1

10 Tage ago | 1