BL_nightly.m

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function [bl_night]=BL_nightly(xSensor,DOY,TOD)
    % establishes initial baseline based on MINIMUM dT value each
    % night (defined by time before 7:00 AM)
    bl_night=[];
    for d=min(DOY):max(DOY)
        DI=find(DOY==d & TOD<700 & isfinite(xSensor'));
        if length(DI)>1
            xDI=xSensor(DI);
            sxDI=sortrows(xDI);
            if length(DI)==floor(length(DI))
                sxDI(end)=[];
            end
            mDI=median(sxDI);
            iDI=find(xDI==mDI);
            if length(iDI)>=1
                bl_night=[bl_night;DI(iDI(1))];
            end
        end
    end
    bl_night=[1;bl_night;length(xSensor)];
    bl_night=unique(bl_night)';
end