rr-interval.zip_ECG MATLAB_ECG signal_RR_ecg rr _to rr entkitty

clc; close all; clear all; load 100_ECG_0_5 ; %The ECG data MAT file END=length(ECG_1); main=ECG_1(1:end,1) ; % first ECG signal % rpeakdetect(main,256) main=transpose(main); slen=length(main); time=(1:slen); % subplot(2,1,1); % plot(time,main,'r'); % [filename, pathname] = uigetfile({'*.xls';'*.*'},'Select file'); % [A,txt,raw]=xlsread(strcat(pathname,filename)); le=input('Enter No. of samples '); samp_freq=input('Enter sampling time'); time=0:1/samp_freq:(le-1)/samp_freq; % main=cell2mat(raw(1:le,1)); plot(time,main); %grid; max=0:0:1000; pos=0.000000:0:1000; distance=0.00000:0:999; c=1; thresh=input('Enter threshold point (check Graph)'); max(c)=main(c); pos(c)=time(c); for i=1:le-1 if main(i)>=thresh if max(c)< main(i) max(c)=main(i); pos(c)=time(i); end if (main(i+1)<=thresh); c=c+1; max(c)=-1000; pos(c)=-1000; end end end d=le+1; max(c)=0; pos(c)=0; c=c-1; for i=1:c-1 distance(i)=pos(i+1)-pos(i); end distance % [fn,pn]=uiputfile('*.xls','Give a Name'); % fileID = fopen([pn,fn],'w'); % fprintf(fileID,'%5f\t\n ',distance); % fclose(fileID); %%%%%%%%%%%%%%MEAN(1ST ORDER CENTRAL MOMENT) OF RR INTERVAL%%%%%%%%%%%%% RRdistance=0; n=length(distance); for (i=1:c-1) RRdistance=RRdistance+distance(i); end meanRR=RRdistance/n %%%%%%%%%%%By direct Formula%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% meanRR=mean(distance) %%%%%%%%%%%%%%%%%%%%%%%%%%%%VARIANCE(2ND ORDER CENTRAL MOMENT)%%%%%%%%%%%%% vari=0; for(i=1:c-1) d(i)=(distance(i)-meanRR)^2; vari=vari+d(i); end vari=vari/(n-1) %%%%%%%%%%%%%%%%%BY direct Formula%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% variance= var(distance) %%%%%%%%%%%%%%%%%STANDARD DEVIATION%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% SD=sqrt(variance); %%%%%%%%%%%%%%%%%%%%%%3RD ORDER CENTRAL MOMENT%%%%%%%%%%%%%%%%%%%%%%%%% m3=0; for(i=1:n) c(i)=(distance(i)-meanRR)^3; m3=m3+c(i); end m3=m3/n; % 3rd order center moment %%%%%%%%%%%%%%%%%%%By direct Formula%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% mm3=moment(distance, 3); % 3rd order center moment %%%%%%%%%%%%%%%%%%%%%%%SKEWNESS%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% m2=variance; skew=m3/(m2)^(3/2) a=skewness(distance) %%%%%%%%%%%%%%%%%MAX OF RR INTERVAL%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% max=distance(1); for(i=1:n) if(max<distance(i)) max=distance(i); end end maxRR=max; %%%%%%%%%%%%%%%%%MIN OF RR INTERVAL%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% min=distance(1); for(i=1:n) if(min>distance(i)) min=distance(i); end end minRR=min; %%%%%%%%%%%%%%%%%%%%%%%R PEAK POSITION%%%%%%%%%%%%%%%%%%%%%% Rpos=pos(1:n); %%%%%%%%%%%%%%%%%%%%%%%Heart Rate%%%%%%%%%%%%%%%%%%%%%%%%%%% %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% % %%%%%%%%%%% check format of data %%%%%%%%%% % [a b] = size(main); % if(a>b) % len =a; % end % if(b>a) % len =b; % end % % %%%%%%%%%% if there's no time axis - make one % if (a | b == 1); % % make time axis % tt = 1/samp_freq:1/samp_freq:ceil(len/samp_freq); % t = tt(1:len); % x = main; % end % %%%%%%%%%% check if data is in columns or rows % if (a == 2) % x=main(:,1); % t=main(:,2); % end % if (b == 2) % t=main(:,1); % x=main(:,2); % end % % %%%%%%%%% bandpass filter data - assume 256hz data %%%%% % % remove mean % x = x-mean(x); % % % FIR filtering stage % bpf=x; %Initialise % if( (samp_freq==128) & (exist('filterECG128Hz')~=0) ) % bpf = filterECG128Hz(x); % end % if( (samp_freq==256) & (exist('filterECG256Hz')~=0) ) % bpf = filterECG256Hz(x); % end % %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% % % %%%%%%%%% differentiate data %%%%%%%%%%%%%%%%%%%%%%%%%%% % dff = diff(bpf); % now it's one datum shorter than before % %%%%%%%%% square data %%%%%%%%%%%%%%%%%%%%%%%%%%% % sqr = dff.*dff; % % len = len-1; % how long is the new vector now? % % %%%%%%%%% integrate data over window 'd' %%%%%%%%%%%%%%%%%%%%%%%%% % d=[1 1 1 1 1 1 1]; % window size - intialise % if (samp_freq>=256) % adapt for higher sampling rates % d = [ones(1,round(7*samp_freq/256))]; % end % % integrate % mdfint = medfilt1(filter(d,1,sqr),10); % % remove filter delay for scanning back through ECG % delay = ceil(length(d)/2); % mdfint = mdfint(delay:length(mdfint)); % % %%%%%%%%% segment search area %%%%%%%%%%%%%%%%%%%%%%% % %%%% first find the highest bumps in the data %%%%%% % max_h = max (mdfint(round(len/4):round(3*len/4))) % % %%%% then build an array of segments to look in %%%%% % %thresh = 0.2; % poss_reg = mdfint>(thresh*max_h); % % %%%%%%%%% and find peaks %%%%%%%%%%%%%%%%%%%%%%%%%%%% % %%%% find indices into boudaries of each segment %%% % left = find(diff([0 poss_reg'])==1); % remember to zero pad at start % right = find(diff([poss_reg' 0])==-1); % remember to zero pad at end % % %%%% loop through all possibilities % for(i=1:length(left)) % [maxval(i) maxloc(i)] = max( bpf(left(i):right(i)) ); % [minval(i) minloc(i)] = min( bpf(left(i):right(i)) ); % maxloc(i) = maxloc(i)-1+left(i); % add offset of present location % minloc(i) = minloc(i)-1+left(i); % add offset of present location % minval2(i)=min(left(i)); % end % q_t=t(left); % q_amp= minval2; % R_index = maxloc; % R_t = t(maxloc); % R_amp = maxval; % S_amp = minval; %%%% Assuming the S-wave is the lowest % %%%% amp in the given window % S_t = t(minloc); % %need=s_t-q_t; % %%%%%%%%%% check for lead inversion %%%%%%%%%%%%%%%%%%% % % i.e. do minima precede maxima? % if (minloc(length(minloc))<maxloc(length(minloc))) % R_t = t(minloc); % R_amp = minval; % S_t = t(maxloc); % S_amp = maxval; % end % length(left) % %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% QRS COMPLEX % % %%%%%%%%%%%% % hrv = diff(R_t); % resp = R_amp-S_amp;