ECG singanal simulation using MATLAB

%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
 h=input('Input your heart rate (in beats per minute)= ');
 p=input('Input desired Peak voltage(in mV)= ');
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%t1=10;
% t1=10 seconds is preferred to enable us have clearer RR tachograms.
% indicates the duration
x1 = p*ecg(6000).' ;
% denoising ecg signals with savitsky-golay filter for us to
% get noiseless or ideal ECG
y1 = sgolayfilt(kron(ones(1,19),x1),0,25);
m = round(h/6);
disp('Number of heart beats per 10 seconds=' )
m
            if h <= 105;
            if m==5;
                n1=32000;
            elseif m==6;
                n1=37000;
                m==7;
                n1=43000;
            elseif m==8;
                n1=49000;
            elseif m==9;
                n1=55000;
            elseif m==10;
                n1=60000;
            elseif m==11;
                n1=66000;
            elseif m==12;
                n1=75000;
           elseif m==13;
                n1=80000;
           elseif m==14;
                n1=85100;
           elseif m==15;
                n1=92000;
            elseif m==16;
                n1=98000;
            else m==17;
                n1=100000;
end
else disp('Heart Rate input exceeds limit')
        end
        n = 1:n1;
        del = round(6000*rand(1));
        mhb = y1(n + del);
        t= linspace(0,t1,n1);
        colordef white;
        plot(t,mhb, 'g');
        q=p+0.5;
        axis([0 t1 -q q]);
        grid; xlabel('Time [sec]');
        ylabel('Voltage [mV]');
        title('Artificial Electrocardiogram');
        legend('Isoelectric line');