function
[RR_mean,QRS_mean,mean_QT,mean_PR,RR_std,RR_skew,RR_kurt,QRS_std,QRS_skew,QRS_ku
rt,std_PR,skew_PR,kurt_PR,std_QT,skew_QT,kurt_QT]=
compute_mean_interval_c(locs_P,locs_Q,locs_R2,locs_S,locs_T,fs)%% WHAT DOES THIS
FUNCTION DO?% THIS FUNCTION COMPUTES THE MEAN RR, MEAN QRS, MEAN QT AND MEAN PR%
INTERVAL BASED ON THE LOCATIONS OF THE PEAKS.% OTHER STATISTICAL DATA ALSO
COMPUTED.% COMPILED AND MAINTAINED BY-% ROHAN SANGHAVI%% CODE LOGIC - RR
INTERVALRR_period = diff((locs_R2))./fs;RR_mean = mean(RR_period); % we consider
the unwindowed mean for accuracyRR_std = std(RR_period);RR_skew =
skewness(RR_period);RR_kurt = kurtosis(RR_period);if isnan(RR_mean) RR_mean =
0;end if isnan(RR_std) RR_std = 0;end if isnan(RR_skew) RR_skew = 0;end if
isnan(RR_kurt) RR_kurt = 0;end %% QRS COMPLEX PERIOD.if
(length(unique(locs_Q))>2 && length(unique(locs_S))>2) if
length(locs_Q)~=length(locs_S) locs_S =
locs_S(~isnan(interp1(unique(locs_Q),unique(locs_Q),unique(locs_S),'nearest')));
% if lengths are unequal endendif (length(unique(locs_Q))>2 &&
length(unique(locs_S))>2) if length(locs_Q)~=length(locs_S) locs_Q =
locs_Q(~isnan(interp1(unique(locs_S),unique(locs_S),unique(locs_Q),'nearest')));
% interpolation to find closest values. endend% double check and then finally
subtract.if length(locs_Q) > length(locs_S) locs_Q1 =
locs_Q(1:length(locs_S)); locs_S1 = locs_S; else locs_S1 =
locs_S(1:length(locs_Q)); locs_Q1 = locs_Q; end QRS_period = ((locs_S1 -
locs_Q1)./fs);QRS_mean = mean(QRS_period);QRS_std = std(QRS_period);QRS_kurt =
kurtosis(QRS_period);QRS_skew = skewness(QRS_period);if isnan(QRS_mean)
QRS_mean = 0;end if isnan(QRS_std) QRS_std = 0;end if isnan(QRS_skew)
QRS_skew = 0;end if isnan(QRS_kurt) QRS_kurt = 0;end %% PR INTERVALif
(length(unique(locs_P))>2 && length(unique(locs_R2))>2) if
length(locs_P)~=length(locs_R2) locs_R2 =
locs_R2(~isnan(interp1(unique(locs_P),unique(locs_P),unique(locs_R2),'nearest'))
); % if lengths are unequal endend if (length(unique(locs_P))>2 &&
length(unique(locs_R2))>2) if length(locs_P)~=length(locs_R2) locs_P =
locs_P(~isnan(interp1(unique(locs_R2),unique(locs_R2),unique(locs_P),'nearest'))
); % interpolation to find closest values. endend if length(locs_R2) >
length(locs_P) locs_R3 = locs_R2(1:length(locs_P)); locs_P2 = locs_P;
temp = 1;else locs_P2 = locs_P(1:length(locs_R2)); locs_R3 = locs_R2;
temp = 1;end PR_interval = ((locs_R3 - locs_P2)./fs);if temp == 0 mean_PR =
mean(PR_interval);else mean_PR = abs(mean(PR_interval));end std_PR =
std(PR_interval);skew_PR = skewness(PR_interval);kurt_PR =
kurtosis(PR_interval);if isnan(mean_PR) mean_PR = 0;end if isnan(std_PR)
std_PR = 0;endif isnan(kurt_PR) kurt_PR = 0;end if isnan(skew_PR) skew_PR =
0;end %% QT INTERVALif (length(unique(locs_Q))>2 && length(unique(locs_T))>2)
if length(locs_Q)~=length(locs_T) locs_T =
locs_T(~isnan(interp1(unique(locs_Q),unique(locs_Q),unique(locs_T),'nearest')));
% if lengths are unequal endend if (length(unique(locs_Q))>2 &&
length(unique(locs_T))>2) if length(locs_Q)~=length(locs_T) locs_Q =
locs_Q(~isnan(interp1(unique(locs_T),unique(locs_T),unique(locs_Q),'nearest')));
% interpolation to find closest values. endend if length(locs_Q) >
length(locs_T) locs_Q2 = locs_Q(1:length(locs_T)); locs_T2 = locs_T;
flag =1; else locs_T2 = locs_T(1:length(locs_Q)); locs_Q2 = locs_Q;
flag =1; % equal hereend QT_interval = ((locs_T2 - locs_Q2)./fs);if flag ==0
mean_QT = mean(QT_interval);elseif flag == 1 mean_QT =
abs(mean(QT_interval));else mean_QT = abs(mean(QT_interval));end std_QT =
std(QT_interval);skew_QT = skewness(QT_interval);kurt_QT =
kurtosis(QT_interval);if isnan(mean_QT) mean_QT = 0;end if isnan(std_QT)
std_QT = 0;end if isnan(skew_QT) skew_QT = 0;end if isnan(kurt_QT)
kurt_QT = 0;end end
