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Chunru


Last seen: 1 jour ago Active since 2013

Matlab user since 1990

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Answered
Getting "Unrecognized function or variable 'reshape'" error!!
%reshape([1 2 3 4],:,1); reshape([1 2 3 4], [], 1) % use [] for auto computed size

1 jour ago | 0

Answered
create 256* 256 matrix with loop values 0 to 7
x = repmat(0:7, 256, 32)

2 jours ago | 0

| accepted

Answered
In the follow screenshot why do we use this filter to our signal I ?
You have a discrete linear system. You could find the system transfer function by analysing the system. It turns out to be a f...

2 jours ago | 0

Answered
Extracting data from confusion matrix fig
f = openfig('SqueezeNet-CM', 'visible'); h = findobj(f.Children(2).Children, 'Type', 'Text'); data = zeros(length(h), 1); for...

2 jours ago | 0

Answered
How to write Exponential growth
x1 = logspace(0, 5, 11) % 11 points btw 10^0 and 10^5 in log space x2 = 10.^(0:.5:5)

3 jours ago | 0

Answered
I am trying to figure out how to plot my data.
Data101 = linspace(0,10,500); red_line = sin(2*pi*Data101)*1.5; for i = 1:length(Data101) if red_line(i) >= 0.95 && red_l...

3 jours ago | 0

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Answered
How to extract multiple 'y' axis values with respect to 'x' axis from .fig file
The figure is likely produced using fplot. The appropriate object handle is of type "ImplicitFunctionLine". f=openfig('imp.fig'...

4 jours ago | 0

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Answered
Plotting a time domain Signal
N=256; f=(0:N-1)/N; xf = 2*sinc(2*f); % 2*sin(w)/w => 2*sinc(2*f) x_i=ifft(xf); plot(f, real(x_i), 'r', f, imag(x_i), '...

4 jours ago | 0

Answered
RMSE heart rate estimation
hrerror = randn(100, 1); % generate some random data hr_rmse =rms(hrerror) % use rms function hr_rmse1 = sqrt(mean(hr...

4 jours ago | 0

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Answered
Shade between lines in log-y scale not properly plot
load data_ecdf figure(1) % just to view the expected filled area semilogy(eOut.psSST, eOut.sSST);grid on;ylabel('mg/L');hold o...

4 jours ago | 0

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Answered
my DCT2 algorithm results in blank image, please help
A = rgb2gray(imread('Lenna.png')); figure; imshow(A); whos B = zeros(64,64); for i = 1:64 for j = 1:64 %Split ...

5 jours ago | 0

Answered
Import numeric data from mixed txt file
a = readtable('data.txt', 'CommentStyle', '#')

5 jours ago | 0

Answered
ifft2 with "symmetric option"
Let F(u, v) be the forward FFT2 of f(x, y). For real function f(x,y), FT exhibits conjugate symmetry, i.e. F(u, v) = F*(-u, -v...

5 jours ago | 0

Answered
Auto adjust y axis with imhist
img = imread('cameraman.tif'); subplot(2,3,1) image(img) colormap('gray') subplot(2,3,2) imhist(img); ylim auto

5 jours ago | 0

Answered
Error using freqz, 6 columns needed to be a valid SOS matrix
freqz is for filter response. use fft or pwelch (or other spectrum estimator) for ploting spectrum of signal. %Generate Sound ...

5 jours ago | 0

Answered
Error in matrix assignment
The image from the file "img" has a size of 256-by-256. However, you have defined the img_stack with size of 128-by-128-by-#of_...

8 jours ago | 1

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Answered
Hypothetical Factorial Question Solution
x = 120; nfact = 1; for i = 1:x nfact = nfact*i; if nfact==x fprintf("%d = %d!\n", x, i) break ...

9 jours ago | 0

Answered
Invert even and odd columns in an image
a = randn(10, 10, 3); imshow(a) % swap even and odd columns b = zeros(size(a)); b(:, 1:2:end, :) = a(:, 2:2:end, :); b(:, 2...

9 jours ago | 1

Answered
why I receive this error "Array indices must be positive integers or logical values"?
gamma = 0.5; beta = 0.9; w = 0.3; r = 1.2; [c1star] = c1a(w,r,gamma,beta) function c1a = c1a(w,r,gamma,beta) % ...

10 jours ago | 0

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Answered
Can I remove zeroth order baseline?
raw = readtable('raw.xlsx'); Xcontractions = raw.rXcont; Ycontractions = raw.rYcont; Time = raw.Time; %% Low-pass filter ...

10 jours ago | 0

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Answered
Multiple bar plot of different datasets in the same figure
x = rand(6,2); b = bar(x); % control the color of individual bar % 1st group first bar b(1).FaceColor = 'flat'; b(1).CDat...

10 jours ago | 1

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Answered
FFT Amplitude and FFT Normalization
There are different ways of interpreting the FT. Here is one way according to Parseval's theorem: or The LHS of the firs...

10 jours ago | 2

Answered
I need ziggurat matlab code to draw
where is a normalizing constant that we can ignore. x = [0:.1:2] y = 1/(2*pi)*exp(-x.^2/2); stairs(x, y, 'b'); hold o...

11 jours ago | 0

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Answered
Find the variation of x(t)
syms x(t) Dx = diff(x, t); eqn = diff(Dx, t) + 7* Dx + 5*x == 8 cond = [x(0)==1, Dx(0)==2]; y = dsolve(eqn, cond) fplot(y, ...

11 jours ago | 0

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Answered
matlab solver with respect to x^2
syms x a y equ1=x^2+x^4==a equ2 = subs(equ1, x^2, y) S=solve(equ1,x) Sx2 =solve(equ2) subs(Sx2, a, 1)

15 jours ago | 0

Answered
How to count the number of white pixels
First, you should use gray scale image. Second you have a large white margin in your data (which is not seen from imshow). You...

15 jours ago | 1

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Answered
How to plug in algebraic equation and solution for it?
It seems that the equation you give has no soltion. f = @(t) 3.7 *( 1 + 4.1*.006/170*(3.7/180)^(2/3) * nthroot(t.^5, 3)).^-1.5;...

15 jours ago | 0

Answered
removing some data in a 4d plot
data = load('4dplot.txt'); % x = 4dplot(:,1); % wrong: variable names canno start with number x = data(:,1);...

16 jours ago | 1

Answered
How to convert a text file into a table properly
Try this: fid = fopen('test.txt', 'r'); fgetl(fid); % skip the header i=1; x = []; while ~feof(fid) s = fgetl(fid); ...

16 jours ago | 0

Answered
What optimizer should I use?
Consider your objective function f(T, R1, R2), whose dependence on R2 lies on the first term only. To minimise f, R2 need to ...

16 jours ago | 0

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