fnirsDataSync.m

function [HbIdx, HbO_epoch_data, HbR_epoch_data, epoch_time] = fnirsDataSync(StartEndIndices, time_filtered, HbO_filtered, HbR_filtered, eventStruct, t0, delay)
    % Authors: Ivy Hill & Iris Li -- rename fnirsTaskTimesSync
    % Created July 9th, 2024 | Last editied July 19th, 2024
    % Purpose: Finds start and end times of each trial, per task (modularized version of split_times section 2):
    for i = 1:(length(StartEndIndices(:, 1))/2) %Iterates accross nav/arm/vs
        for j = 1:length(StartEndIndices(1, :)) %Iterates by trial number

            sidx = StartEndIndices(2*i - 1, j); % odd rows
            eidx = StartEndIndices(2*i, j); % even rows

            sampleTimes = eventStruct.time_stamps([sidx, eidx]) - t0 - delay; %Pulls the indices from the Unity sample times

            %Essentially syncs Unity sample rate and fNIRS sample rate
            HbIdx(i, j, :) = interp1(time_filtered,1:length(time_filtered),sampleTimes,'nearest'); %Interpolates the nearest fNIRS time to the Unity sample time

            %Sorts values as a fourth dimentional cell array to combine
                %vectors/matricies of varying sizes and to make easier to turn
                %into a table in future
            HbO_epoch_data(i, j, :, :) = {HbO_filtered(:, [HbIdx(i, j, 1):HbIdx(i, j, 2)])};
            HbR_epoch_data(i, j, :, :) = {HbR_filtered(:, [HbIdx(i, j, 1):HbIdx(i, j, 2)])};
            epoch_time(i, j, :) = {time_filtered(HbIdx(i, j, 1):HbIdx(i, j, 2))};
            epoch_time{i, j, :} = epoch_time{i, j} - epoch_time{i, j}(1);
        end
    end
end