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Using cellfun for multidimensional cell

I have a cell of this type: 200×3 cell array [1×60000 double] [ -0.9365] [154.9924] [1×60000 double] [ 10.8080] [297.1132] [1×60000 double] [ 15.5680] [121.3598] Etc. I want to use the cusum function, where the second column and third columns are inputs. For a single row this would be: cusum(this_cell{j}, constant, constant, this_cell{j,2}, this_cell{j,3}) What would be syntax for using cellfun? ANSWER Matlabsolutions.com provide latest MatLab Homework Help, MatLab Assignment Help for students, engineers and researchers in Multiple Branches like ECE, EEE, CSE, Mechanical, Civil with 100% output.Matlab Code for B.E, B.Tech,M.E,M.Tech, Ph.D. Scholars with 100% privacy guaranteed. Get MATLAB projects with source code for your learning and research. I don't have the Signal Processing Toolbox , so I can't access the cusum function. However, here is a generic example of using three inputs into cellfun, that yo...

Comb filtering when sampling frequency is not multiplicative of the interference fundamental frequency

Hi all, I would like to apply a notch comb filter (e.g. by using the iircomb function), but my sampling frequency is 976 Hz and the fundamental frequency of the noise signal is 50 Hz. Any ideas of how I could achieve that would be greatly appreciated. An alternative would be to use multiple notch filters (e.g. iirnotch) but this would increase dramatically the associated computational costs. ANSWER Matlabsolutions.com provide latest MatLab Homework Help, MatLab Assignment Help for students, engineers and researchers in Multiple Branches like ECE, EEE, CSE, Mechanical, Civil with 100% output.Matlab Code for B.E, B.Tech,M.E,M.Tech, Ph.D. Scholars with 100% privacy guaranteed. Get MATLAB projects with source code for your learning and research. You have to change the Sampling frequency such that you can get the sampling frequency to be a multiple of noise frequency. You can do this my a combination of down-sampling and up-sampling. Find a fract...

How to deal with this error??

A model of the surface EMG signal is created by filtering a white gaussian noise, using a shaping filter H(f). this filter has low cut-off freq=60hz and high cut-off freq=120hz. this is my code but i don't know how to deal with Undefined function 'designfilt' for input arguments of type 'char' . clear all; subplot(322); load nnoise.m; plot(nnoise,'k'); % design shaping filter bpFilt = designfilt('bandpassfir',... 'CutoffFrequency1',60,'CutoffFrequency2',120, ... 'SampleRate',2000); subplot(323); W = filter(bpFilt,nnoise); plot(W,'k');title ('EMG'); ANSWER Matlabsolutions.com provide latest MatLab Homework Help, MatLab Assignment Help for students, engineers and researchers in Multiple Branches like ECE, EEE, CSE, Mechanical, Civil with 100% output.Matlab Code for B.E, B.Tech,M.E,M.Tech, Ph.D. Scholars with 100% privacy guaranteed. Get MATLAB projects ...

FindPeaks() of a 1024 x 116 Matrix

I have a matrix that I read into MatLab that is 116 spectra (columns) each being 1024 elements (rows). Each spectrum has a peak and I'm looking to determine the following information from each spectrum: - Peak value - Peak position - Peak width at a set height, like 10% or 30% of the peak height. What I'd really like is to know the first and last x element of each peak I've completed the Signal Processing Toolbox course and it didn't go over the FindPeaks() function. Please, any help would be greatly appreciate. Even if it's direction to a good source on the function. Thank you! ANSWER Matlabsolutions.com provide latest MatLab Homework Help, MatLab Assignment Help for students, engineers and researchers in Multiple Branches like ECE, EEE, CSE, Mechanical, Civil with 100% output.Matlab Code for B.E, B.Tech,M.E,M.Tech, Ph.D. Scholars with 100% privacy guaranteed. Get MATLAB projects with source code for your learning and research. findpeaks only...

Sum five elements before a specific number

Hi, I used "findpeaks" to find the IDs of all the peaks in my data. I need for each peak to find the average of five elements before it. the problem is that some of the peaks don't have five elements before it (say the second value is a peak, therefore, there is only one value before it). How can I tell matlab to average whatever is available but not more than 5 elements? ANSWER Matlabsolutions.com provide latest MatLab Homework Help, MatLab Assignment Help for students, engineers and researchers in Multiple Branches like ECE, EEE, CSE, Mechanical, Civil with 100% output.Matlab Code for B.E, B.Tech,M.E,M.Tech, Ph.D. Scholars with 100% privacy guaranteed. Get MATLAB projects with source code for your learning and research. data_before = Yourdata(max(1, idx-5) : idx-1) Note that in the case that idx is 1, this will give the empty result, as "empty" is all of the data that is available before the location.

Trying to make a chirp (sweep) in matlab with random frequency

Hi guys! I have been trying to make a chirp function in which the frequency is changing randomly through the time my parameters are this t1=0 t2=1 f1=0 f2=60 I have tried the chirp function of matlab, however, the frequency is linearly increasing but I also want that it could decrease. Any ideas? Thanks in advance ANSWER Matlabsolutions.com provide latest MatLab Homework Help, MatLab Assignment Help for students, engineers and researchers in Multiple Branches like ECE, EEE, CSE, Mechanical, Civil with 100% output.Matlab Code for B.E, B.Tech,M.E,M.Tech, Ph.D. Scholars with 100% privacy guaranteed. Get MATLAB projects with source code for your learning and research. It's not really a chirp if you want to have the frequencies vary more or less randomly up and down. But anyway, to make a signal with random frequencies: t = linspace(0, 100, 400); amplitude = 3; % Make random frequencies. frequency = .0...

question about the signal smoothing example

Hello, I have a question about the signal smoothing example given in the documentation of Matlab. load bostemp days = (1:31*24)/24; plot(days, tempC) axis tight ylabel('Temp (\circC)') xlabel('Time elapsed from Jan 1, 2011 (days)') title('Logan Airport Dry Bulb Temperature (source: NOAA)') I understand that this example wants to emphasize that the measurements are taken 24 hours a day, 31 days for January. So the variable 'days' ranges from 1 to 31*24. But why divide it by 24? Also, hoursPerDay = 24; coeff24hMA = ones(1, hoursPerDay)/hoursPerDay; avg24hTempC = filter(coeff24hMA, 1, tempC); plot(days,[tempC avg24hTempC]) I understand that this example refers to the moving average of length N (in this case N = 24). I don't understand why there is a need to set N = 24. Why can't it be just N = 1? ANSWER Matlabsolutions.com provide latest MatLab Homework Help, MatLab Assignment Help for students, engineers and res...

error in returning widths over iterated findpeaks

Hi, I am trying to use findpeaks over a matrix, x, column by column. I am using a for loop as below: for k=1:size(x,2) [P{k},locs{k},widths,proms{k}]=findpeaks(x(:,k)) end Everything is working fine except for returning widths. P, locs and proms all return as cell arrays with all the data for the peaks in each column. However, widths only returns the widths of the peaks for the last column. When I try to edit it by making widths return as a cell array: for k=1:size(x,2) [P{k},locs{k},widths{k},proms{k}]=findpeaks(x(:,k)) end I get the error message "Cell contents assignment to a non-cell array object" Is there a way to get this function to return all the widths of all the peaks for each column? ANSWER Matlabsolutions.com provide latest MatLab Homework Help, MatLab Assignment Help for students, engineers and researchers in Multiple Branches like ECE, EEE, CSE, Mechanical, Civil with 100% output.Matlab Code for B.E, B.Tech,M.E,M.Tech, Ph.D...

collect 400 samples from a LFM (5MHz bandwidth) signal modulated on 18GHz

f_sweep = 5e6; fs = f_sweep * 4.121; sLFM = phasedLinearFMWaveform('SampleRate',fs,'SweepBandWidth',f_sweep,'PulseWidth',1e-3); lfmwav = setp(sLFM); collector = phase.WidebandCollector('Sensor',URA, 'SampleRate',fs,'CarrierFrequency',18e9); S1=awgn(lfmwav,-10,'measured'); Y=collector(S1(1:400),[20;30]); ANSWER Matlabsolutions.com provide latest MatLab Homework Help, MatLab Assignment Help for students, engineers and researchers in Multiple Branches like ECE, EEE, CSE, Mechanical, Civil with 100% output.Matlab Code for B.E, B.Tech,M.E,M.Tech, Ph.D. Scholars with 100% privacy guaranteed. Get MATLAB projects with source code for your learning and research. Your sampling rate is set at fs, which is about 20 MHz, this means your Nyquist is about 10 MHz, regardless what your carrier is, i.e., your signal is aliased. If you want to see 18 GHz at the center, you will have to sample at 36 GHz, this is obviously very expensive. SE...

fft dim parameter when ndims(x) > 2

fft dim shows how dim parameter is used for multidimensional signals of ndims(X) = 2 When ndims(X) > 2 how is it used? (I cannot use fftn here.) ANSWER Matlabsolutions.com provide latest MatLab Homework Help, MatLab Assignment Help for students, engineers and researchers in Multiple Branches like ECE, EEE, CSE, Mechanical, Civil with 100% output.Matlab Code for B.E, B.Tech,M.E,M.Tech, Ph.D. Scholars with 100% privacy guaranteed. Get MATLAB projects with source code for your learning and research. If you have a multidimensional array x, say x = ones(3,4,5) then fft(x,[],3) will perform FFT on the dimension with 5 elements, and so on.

How to calculate period of signal with matlab

Hi , I have the signal x2(t)=|cos(10*pi*t)|.How can i calculate its period with matlab?I am new matlab so each help will be usefull ANSWER Matlabsolutions.com provide latest MatLab Homework Help, MatLab Assignment Help for students, engineers and researchers in Multiple Branches like ECE, EEE, CSE, Mechanical, Civil with 100% output.Matlab Code for B.E, B.Tech,M.E,M.Tech, Ph.D. Scholars with 100% privacy guaranteed. Get MATLAB projects with source code for your learning and research. use autocorrelation. If your data is periodic you should get high correlation once the lag time matches the period. here is an example: x=0:0.1:20*2*pi; y=sin(x); % so we know the period is 2*pi roughly 6.28 ac=xcorr(y,y); [~,locs]=findpeaks(ac); mean(diff(locs)*0.1) ans = 6.2842 In a more complex data set including some noise you need to work around the find peaks a little bit. That might be too noisy.

Finding Accurate Amplitude Using FFT

I have been working on code to use the FFT to find the amplitude of a signal. However, despite my best efforts to window I seem to get incorrect amplitudes. When I manually find Amplitude by inspecting the signal I get A = 63.7. When I use the following code I get A = 54.8. This is causing significant errors in my Bode plot. I tried using a flat top window to maximize amplitude accuracy. My signal does not seem significantly noisy. I expected an amplitude much closer to the true value. function Amplitude = Gaindb(x) if size(x, 2) > 1 x = x'; end x = x - mean(x); N = length(x); win = flattopwin(N); x = fft(x.*flattopwin(N)); Amplitude = 2*max(abs(x))/N; end ANSWER Matlabsolutions.com provide latest MatLab Homework Help, MatLab Assignment Help for students, engineers and researchers in Multiple Branches like ECE, EEE, CSE, Mechanical, Civil with 100% output.Matlab Code for B.E, B.Tech,M.E,M.Tech, Ph.D. Scholars with 100% privacy g...