Community Profile # Manolis Michailidis

### Alexander Technological Institute of Thessaloniki

Active since 2015

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Error in testing neural
i just found my error, the test matrix should have the same dimensions as the train

meer dan 7 jaar ago | 0

Question

Error in testing neural
Hello, i have trained my neural with matrix X [40 30] the Target is [3 30]. Now i have Test matrix [4 10] and every time i try t...

meer dan 7 jaar ago | 1 answer | 0

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Understanding neural networks with patternet
Hello, i am new to neural networks and find it difficult to understand a few things about them. First of all i have created wi...

meer dan 7 jaar ago | 1 answer | 0

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Split signal if there are zero values
Hello, my task is simple i want to divide my signal into number x parts, where x is when the difference between the last nonzero...

meer dan 7 jaar ago | 1 answer | 0

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Code including multiply embedded for loops with conditions
Hello, i have a signal (nfo) and having found its peaks (pks) and minima (val) i should do the following : If it starts with pea...

bijna 8 jaar ago | 0 answers | 0

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Extending a vectors length with zeros
Lets assume x(1x3) and y(1x8) Padd=[x,zeros(1,length(y)-length(x))];

bijna 8 jaar ago | 1

How to calculate moving standard deviation in a matrix?
Take a look here <http://www.mathworks.com/matlabcentral/fileexchange/9428-movingstd-x-k-windowmode->

bijna 8 jaar ago | 0

create a while loop: while all values in a matrix are positive(code)
You can use the absolute value abs function , or if there are some non positive, by mistake, you can say a(a>0); where...

bijna 8 jaar ago | 0

Extract the data vectro from cftool
For everyone having the same issue i found a bypass way. Although after i plot the data and when i zoom in i can see clearly the...

bijna 8 jaar ago | 1

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how to show a velocity vector at any two point in matlabs on path curve.also acceleration vector at any two point on velocity curve.
If this is the case ou can use plot and hold on to achieve it. t=( 0:0.01:3); x = t.*exp(-3*t)+0.25*exp(-3*t); v=exp(...

bijna 8 jaar ago | 0

Question

Extract the data vectro from cftool
Hello, i have performed curve fitting with cftool , but i cannot accomplish to extract the smoothed data as vector. Instead i ca...

bijna 8 jaar ago | 1 answer | 0

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How to write a loop for vectors?
Hello, the main issue is that in your loop you should use cell because for every iteration you have different dice results and t...

bijna 8 jaar ago | 0

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Divide time series into regions
Hello, i have a graph with rapidly changes and i need to divide it into regions like are shown in the picture <</matlabcentra...

bijna 8 jaar ago | 2 answers | 0

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Normalized cross-correlation function
Hello, i am trying to write a normilized cross-correlation method function , but i can't complete it. Here are the details of th...

ongeveer 8 jaar ago | 3 answers | 0

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How do I solve this?
See hold <http://www.mathworks.com/help/matlab/ref/hold.html> .

ongeveer 8 jaar ago | 0

How can I divide an audio signal into overlap frames and take FFT to the signal?
There is a function called spectrogram which does what you want , see the related documentation <http://www.mathworks.com/help/s...

ongeveer 8 jaar ago | 0

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help with nested indexing
Hi, my problem is not difficult but i am getting confused about it. So i have two vectors of indexes Nzlocs and locs ...

ongeveer 8 jaar ago | 1 answer | 0

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Hello, i need to read multiply audio files so i wrote for idx=1:Num filename =['my_dir\data\a',int2str(idx),'.wav']...

ongeveer 8 jaar ago | 1 answer | 0

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Delete empty cell array
have you tried something like this? for i=1:length(your_cell_size) idx(i) = find(~cellfun(@isempty,A{i})); ...

ongeveer 8 jaar ago | 0

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Filter signals with variety in noise level
Hello, i am working in a project where i track the fundamental frequency (f0) of a signal using autocorrelation. The algorithm w...

ongeveer 8 jaar ago | 1 answer | 0

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How can i randomly move the values of a vector
use randperm take a look here http://www.mathworks.com/help/matlab/ref/randperm.html

ongeveer 8 jaar ago | 1

| accepted

Question

Find with condition in loop can't create cell array
Hello, i have to crate a new vector that will have the different number of peaks in each row for each pulse. So i have this grap...

ongeveer 8 jaar ago | 1 answer | 0

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How to segment an wav file off to 2 second interval and FFT every 2 second.
There is the spectrogram take a look here <http://www.mathworks.com/help/signal/ref/spectrogram.html> which performs STFT. Also ...

ongeveer 8 jaar ago | 0

Submitted

Submitted

Find valleys (minima) in mono signal
Finds the local minima and their locations Question

frequency modulation sinwave with 3 different frequencies
Hi, i want to make a sinwave that will change his frequency 3 times (like in the picture i uploaded <</matlabcentral/answers/...

meer dan 8 jaar ago | 0 answers | 0

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Custom Triangle with up/down slopes , help
Hello i want to make a coustom triangle without using the existing function of matlab, which will start lets say at 300 and will...

meer dan 8 jaar ago | 1 answer | 0