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Greg Dionne


MathWorks

146 2012 年以降の合計貢献数

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How to edit original data in for-each equivalent statement
You can often avoid the need for references and the for-loop altogether in MATLAB. This example should get you started: classd...

5日 前 | 0

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Segmentation of audio signal.
If you have the Signal Processing Toolbox, buffer may be what you're after. Hope this helps! -Greg

4ヶ月 前 | 0

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RMS Function Returns NAN
It's likely you have NaN in your input, or your input is an empty vector. If you wish to exclude NaN values from computation, t...

4ヶ月 前 | 0

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thd() in matlab workspace shows me an unexpected result, is anything wrong ?
The default window used when running the THD function has a wide rolloff which masks the second and third harmonics in your sign...

5ヶ月 前 | 2

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Why this bandpass butterworth is unstable (while the corresponding low and high pass are stable)?
You will have better results if you use second-order sections. See the "Limitations" section of https://www.mathworks.com/help/...

5ヶ月 前 | 1

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medfreq with delta-F threshold ?
From what I can tell your sinusoid is around ~895 Hz and has fairly clean second and third harmonics. So I took that as the sta...

5ヶ月 前 | 0

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measure time from fft spectrogram
You can extract the time vector from the third output of the spectrogram function. [S,F,T,Pxx] = spectrogram(X,...) F is the...

5ヶ月 前 | 0

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Fast Fourier Transform of the subtraction between a signal and the same signal but shifted
Circularly shifting in the time domain is equivalent to multiplying by a phase ramp in the frequency domain. The FFT of the va...

6ヶ月 前 | 1

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How to get pairwise distance matrices from dynamic time warping dtw on a matrix of time series ?
Your signals look extremely well time-aligned (within a sample). Since you have NaN, I suppose you could just perform a weigh...

6ヶ月 前 | 0

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Warping window in "findsignal()" for dtw as TimeAlignment.
At the moment there are no warping constraints used in the FINDSIGNAL variant of DTW. I'm usually successful at coaxing it to...

6ヶ月 前 | 0

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FFT of Downsampled Signal
Hi Adam, If you have significant noise on the signal, then decimate(x,10) or resample(x,1,10) would be preferable. Your result...

6ヶ月 前 | 1

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Making a video showing trajectories of particles
This should get you started: load Trajectories.mat hAxes = newplot; colors = lines(10); axis(hAxes,[0 1300 0 1100]) f...

6ヶ月 前 | 0

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DSP TOOL BOX NOT WORKING Spectrum Analyzer For Two-Sided Power Spectrum
This worked for me: sin = dsp.SineWave('Frequency',100,'SampleRate',1000); sin.SamplesPerFrame = 1000; scope = dsp.SpectrumAn...

7ヶ月 前 | 1

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Generating a sound that goes up and down in frequency - based on a vector of numbers
Hi Harriet, I'm glad you have the Signal Processing Toolbox and were successfully able to use vco, resample, and spectrogram to...

8ヶ月 前 | 0

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Weighted spline for calculating trajectory with lowest possible lateral acceleration
I'm not certain if I understood your question correctly, but you could try adapting the approach in the drivingScenario trajecto...

8ヶ月 前 | 0

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How to select matching records based on the differences in their detection time?
I think you want something like this(?): function [t1s, t2s] = szanto(t1, t2) % compute time vectors offset from first tim...

8ヶ月 前 | 0

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How to find the slope of phase data (between two points) which is uneven
You could try a combination of <https://www.mathworks.com/help/matlab/ref/unwrap.html unwrap> (to remove the jumps of your array...

12ヶ月 前 | 0

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Looking for a way to patch 44k polygons fast
Have you tried using just one patch? You can specify X and Y as matrices (this example taken from the doc page on <https://www....

約1年 前 | 0

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how to apply dynamic time wrapping
DTW(X,Y) can work on vectors of non-equal length. It will repeat elements in either X or Y so that the comparison is of the sam...

約1年 前 | 0

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How can I determine the diameter (inner and outer) of the ring profile?
Try this link: <https://www.mathworks.com/help/images/detect-and-measure-circular-objects-in-an-image.html>

約1年 前 | 0

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Why does findchangepts doesn't work right?
If you have R2016b or later try: Fs = 100; [sst,f] = fsst(Ch9,Fs,kaiser(512,10)); fridge = tfridge(sst,f,10,'NumRidge...

約1年 前 | 1

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Time response of the voltage
Most of the documentation for the bilevel measurements panel can be found here: <https://www.mathworks.com/help/simulink/ug/bile...

約1年 前 | 0

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ismember runs too slow (others have asked similar questions)
Looks like your positional data could fit in a 3-D histogram (168x24x168). This could be made considerably faster, but hopefull...

約1年 前 | 1

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plot a smooth envelope for oscillation curves
Do you have a particular selection criteria for the peaks or formula for how you would like the smoothing performed at the ext...

約1年 前 | 0

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How to combine Matlab's build-in functions dtw and pdist?
You'll want to take the output of DTW and put it into a form that PDIST can recognize. This should get you started: func...

約1年 前 | 1

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Filter big data simulink or matlab
<https://www.mathworks.com/help/signal/ref/hampel.html hampel> should get you started plot(hampel(OutAIS.Data)) If you n...

1年以上 前 | 1

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colthoid fitting using trajectory();
The trajectory generator uses a fast discrete solver to obtain a G2-continuous path, so some discontinuities (usu < 1 degree/met...

1年以上 前 | 0

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How can i delay a signal?
You could do something simple like: s = exp(-a*(t-t0)).*sin(2*pi*(t-t0)/T); and tweak t0 to be whatever time you need th...

1年以上 前 | 0

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Power Spectrum of Colored Noises
I think you're looking for a PSD. Try |periodogram(white_noise)| or |periodogram(white_noise,[],[],Fs)|

1年以上 前 | 0

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Why i can't plot a spectrum of a rectangular window function?
If you line up the frequency points, you'll see that your FFT is showing the zeros only. If you crank up the number of points i...

1年以上 前 | 0

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