Split Data Into Parts

%% I have a set of table data of different columns of a patients data. I intend to split the data into various zones using the Breathing Pattern values.

In this case, I have plotted the Oxygen Level as rises and falls.

So I intend to split the Breathing Readings into 4 zones.

-First Zone when it is below a certain threshold say >100, (See Image from 0 - 1300 seconds)

- Second Zone when Oxygen Levels go from 100 to 500 (from 1301 - 1400 seconds)

- Third Zone when it drops from 500 to 100 (from 1401 - 1650 seconds)

- Fourth Zone when it goes below (1651 seconds - end)

N.B. I have another variable that could tell me when there is not signifcant breathing activity (ie. for First and Fourth Zone) if this would be need to increase the fidelity of the first and fourth zone

I tried to use mat2cell to split and do my 4 plots but I don't seem to get the hang of it.

%Converting Table to Matrix

dataAllMatrix = table2array(dataAll);

%% Plot Data for One Patient

PatientNumber = 75;

% 'end -1' (24 columns - 1 = 23)

PatientNumber_idx = find(dataAllMatrix(:,end-1)== PatientNumber);

Time = dataAllMatrix(PatientNumber_idx(1):PatientNumber_idx(end),1);

Oxygen_Level = dataAllMatrix(PatientNumber_idx(1):PatientNumber_idx(end),24);

figure

plot (Time, Oxygen_Level);

xlabel('Time(s)')

ylabel('Oxygen Level (mol)')

Patient_Title = ['Patient ', num2str(PatientNumber)];

title(Patient_Title)

%% Split Patient's Oxygen Level Data to 4 Zones (BP_area_1, BP_area_2, BP_area_3, BP_area_4)

Zone_1 = find(Oxygen_Level(:, end) < 100);

C = mat2cell(Oxygen_Level, Zone_1)

plot (C)

Answer 1

[Alan Stevens]

Aren't there five zones? Identify by something like:

z1 = find(oxygenlevel>100,'first');  % index to end of first zone
z2 = find(oxygenlevel>500,'first');  % index to end of second zone/start of third zone
z3 = find(oxygenlevel>500,'last');   % index to end of third zone/start of fourth zone
z4 = find(oxygenlevel>100,'last');   % index to end of fourth zone/start of last zone

t1 = Time(1:z1);   % times in zone 1
t2 = Time(z1:z2);  % times in zone 2
t3 = Time(z2:z3);  % times in zone 3
t4 = Time(z3:z4);  % times in zone 4
t5 = Time(z4:end); % times in zone 5

% etc.

[Amadi Gabriel Udu]

Yes. There are 5 zones. I have given a clearer representation with the y-axis labels

[Amadi Gabriel Udu]

I get an error, saying

'Second argument must be a positive scalar integer'.

I was trying to also make a plot of the first zone

[Alan Stevens]

Without the actual data, it's not really possible to help further!