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Chunru


Last seen: Today Active since 2013

Matlab user since 1990

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Answered
How to convert negative numbers in parentheses (bank-formatted text) to numbers with minus sign?
xbank = [" (1,234)" "2,345,678" "(1,234.56)"] x = arrayfun(@bank2double, xbank) function x = bank2double(s) s...

alrededor de 14 horas ago | 0

Answered
Combine mat files into one, then combine all variables into one
filename = ["abc001.mat" "def002.mat"]; % list of the files in order variable1all = []; variable2all = []; for i=1:leng...

3 días ago | 0

Answered
there is nan in a column, delete the whole row
idx = isnan(c.lagpe); % find the index of nan c(idx, :) =[]; % remove the rows from table

3 días ago | 0

| accepted

Answered
How can I automate a process for n times?
J = [14 0 0 0 0; 15 0 0 0 0; 16 16 16 0 0; 22 22 0 0 0; 24 24 0 0 0; 25 25 25 25 25] Lr = size(J,1); for i = 1:Lr row = J...

4 días ago | 1

Answered
Program code for convolution
u = [1 2 3 1]; v = [2 3]; conv(u, v) % filter(u, 1, v)

5 días ago | 0

Answered
plotting a surface on a cylinder top face
theta =0:0.01*pi:2*pi; r=0.8; x=r*cos(theta); y=r*sin(theta); z=zeros(size(x)); % simple patch for base p_base =patch(x,...

5 días ago | 0

Answered
How to remove cell data from specific column using dates as a reference?
T = readtable("https://www.mathworks.com/matlabcentral/answers/uploaded_files/1085695/flowrate_dates.xlsx", "Sheet", 3) idx = T...

6 días ago | 0

Answered
combine two cell into one string
t = readtable('https://www.mathworks.com/matlabcentral/answers/uploaded_files/1085370/SummaryResult%20-%20Copy.xlsx'); t = t(1:...

6 días ago | 0

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Answered
Echo+noise signal
% generate a waveform f0 =100; fs=1000; pw = 0.1; pri = 1; npulses = 10; s = cos(2*pi*f0*(0:1/fs:pw))'; % it can be ...

6 días ago | 1

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Answered
Spectogram Of I and Q data
x = xi + 1i*xq; spectrogram(x)

7 días ago | 0

Answered
Transfer Quarterly dates to Monthly
% Your data dtstr = ["31/3/1992" "30/6/1992" "30/9/1992" "31/12/1992"]; x = [1.2 1.3 1.4 1.5]...

7 días ago | 0

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Answered
What is the training accuracy of this model?
If Labels is character array instead of string array, then numel(Labels) will give the number of characters instead of the numbe...

7 días ago | 0

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Answered
Get coordinates points inside a 3-D circle in MATLAB
normal=[-3.5556 -0.2222 1.0000]; center=[138 146 219]; radius=3; plotCircle3D(center,normal,radius); hold on point = p...

7 días ago | 0

Answered
How can I label multiple routes on a geoscatter plot?
fig = figure; %pos = fig.Position; %files = dir('cast*.gpx'); for i = 1:5 %length(files) %filename = files(i).name; ...

9 días ago | 0

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Answered
operation on single elements in MATLAB
x=-2:1:2; %coordinates x y=x.^2; %coordinates y z=[x;y] d = diff(z, 1, 2) % diff along 2nd dim d = vecnorm(d...

10 días ago | 1

Answered
specifying frequencies in pwelch not working
No problem for on-line matlab. data = randn(20000,1); %assume this is 1 row of my EEG data of interest analysisWinSize = 1000...

10 días ago | 0

Answered
Create duration array template
ti = duration('00:00:0.00','Format','hh:mm:ss.SSS'); tf = duration('02:00:0.00','Format','hh:mm:ss.SSS'); interval = millise...

10 días ago | 0

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Answered
Multiply values in array by *-1
a = randn(1, 106); a(14:20) a(16:18)=-a(16:18); a(14:20)

11 días ago | 0

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Answered
How to find sum of previous 5 numbers in a column..
x = [56 45 56 678 678 568 2 3 4 5]; y = filter(ones(5,1), 1, x) y1 = y(5:end)

11 días ago | 0

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Answered
Graph function problem Incorrect values
What's wrong? x=[0:50]; y=-x.^3+3*x.^2+2*x-27; plot(x,y)

11 días ago | 0

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Answered
How to reduce running time of diagonal matrix multiplication with full matrix in Matlab?
n = 2000; d=500; B = randn(d, n); dv = randn(n, 1); D = diag(dv); % Normal tic A = B*D*B'; toc % Speed up 1 tic C = ...

11 días ago | 0

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Answered
How to make a number NaN when its both neighbours are NaN?
A = [NaN 2.35 NaN 2.358 1.68 1.98 2.88 NaN 2.68 NaN 2.70 NaN 2.20 NaN 3.03; NaN NaN 2.77 NaN 2.67 1.87 2.56 1.88 2.39 NaN...

11 días ago | 0

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Answered
adding an if condition so the negative value would be set to zero
for i=1:length(t) DOD(i)=cumsum((T(i)*30)/(3600*14.6)); end DOD = max(DOD, 0)

11 días ago | 0

Answered
Circular bar graph in matlab
% Some data T.Country = string(('A':'Z')'); T.Population = randi([1000 10000], size(T.Country)); T = struct2table(T); n = he...

11 días ago | 1

Answered
Plot with break in curve
xy=[0.0000 -963.0477 0.0043 -961.9818 0.0085 -960.8602 0.0128 -959.6834 0.0171 -958.4515 0.0214 -957.16...

12 días ago | 0

Answered
removing the pixels with different size and unregular shape
A simple approach is to find the regions you want to deleted (assign 0). Four your question, rectangle regions are sufficient: ...

12 días ago | 1

Answered
How to plot like this graph?
% [1 2][3 4] % [6 7] h(1) = subplot(2, 4, [1 2]); % 4x2 grid, 1st subplot plot(randn(10, 1)); h(2) = subplot(2, 4, ...

12 días ago | 0

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Answered
Error using mesh Z must be a matrix, not a scalar or vector. Error in untitled6 (line 5) mesh(W,Y,Z)
w = 200:50:450; y=120:30:240; [W,Y] = meshgrid(w,y); Z= 64.0189+1.4629*W-2.626*Y-0.0012*W.^2+0.0098*W.*Y+0.0082*Y.^2; whos ...

13 días ago | 0

Answered
How to read .XY file?
file='random_x.txt'; fid = fopen(file, 'rt'); i=1; s1 = ''; while ~feof(fid) s{i} = [s1 fgetl(fid)]; %...

13 días ago | 0

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Answered
regexp function - get index of string with two conditions
str = {'strawberry/banana#(';'apple#,melon*cherry';'apple_banana_cherry'}; s = regexp(str, '^apple.*(cherry)$', 'match'); id...

13 días ago | 0

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