trimming start end end of time series data in matlab 2015

조회 수: 7 (최근 30일)
THONTI BEERAIAH
THONTI BEERAIAH 2020년 10월 6일
편집: Rohit Pappu 2020년 10월 28일
I have a program as below
close all;
clear all;
clc;
%%loading the data
fs=240;%sampling frequency
sl=dlmread('Sepfourtyfivemmsl.dat');
sr=dlmread('Sepfourtyfivemmsr.dat');
%%transforms of left oscillator
z1=hilbert(sl);
instant_amplitude = abs(z1);
instant_phase = unwrap(angle(z1));
instant_freq = diff(instant_phase)/(2*pi)*fs;
%% Transformatons of right oscillator
z2=hilbert(sr);
inst_amplitude = abs(z2);
inst_phase = unwrap(angle(z2));
inst_freq = diff(inst_phase)/(2*pi)*fs;
for i=1:2000
norm_intensitysl(i)=sl(i)/instant_amplitude(i);
norm_intensitysr(i)=sr(i)/inst_amplitude(i);
end
for i=1:1999
sumsl=0;sumsr=0;
sumsl=sumsl+instant_freq(i);
sumsr=sumsr+inst_freq(i);
end
meansl=sumsl/1999;
meansr=sumsr/1999;
mean_rel_freq=meansl-meansr;
%%relative values
rel_phase=abs(instant_phase-inst_phase);
rel_freq=abs(instant_freq-inst_freq);
%%plotting results
%subplot(211)
plot(norm_intensitysl,'g');
title('Normalised intensity');
xlabel('Number of framse');
ylabel('Intensity');
hold on;
plot(norm_intensitysr,'r');
legend('left oscillator','right oscillator');
by running above code I am getting a graph like below
here I want to trim first 200 frames and last 200 frames so at line 20 in above program I modified like
for i=200:1800 and got a graph like below
could you please tell me what mistake I did and how to smooth the data by trimming starting and end time series

채택된 답변

Rohit Pappu
Rohit Pappu 2020년 10월 28일
편집: Rohit Pappu 2020년 10월 28일
There are two possible sources of errors when the number of frames is reduced -
  1. The for loop used to calculate sumsl and sumsr is supposed to contain 1599 iterations instead of 1999. So it should be for i=201:1799 (Line 26)
  2. The denominator value of meansl and meansr should be 1599 instead of 1999 , since only 1599 values are being used to calulate sumsl and sumsr (Line 31 and Line 32)

추가 답변 (0개)

카테고리

Help CenterFile Exchange에서 MATLAB에 대해 자세히 알아보기

Community Treasure Hunt

Find the treasures in MATLAB Central and discover how the community can help you!

Start Hunting!

Translated by