Question

In MATLAB, Plot the normal distribution, display the equation for the normal distribution on the graph (see the 1st equation on Wikipedia), and display the location for the mean and draw a vertical line at the mean plus and minus one standard deviation. Pick for the mean 17 and for the standard deviation e. Label the axes.

Answer 1

>> x = randn(10000,1);
>> histfit(x)
hist(data,5)
mu=mean(data);
sg=std(data);
x=linspace(mu-4*sg,mu+4*sg,200);
pdfx=1/sqrt(2*pi)/sg*exp(-(x-mu).^2/(2*sg^2));
plot(x,pdfx);
STD = 1;
MEAN = 2;
x = -4:0.1:4;
f = ( 1/(STD*sqrt(2*pi)) ) * exp(-0.5*((x-MEAN)/STD).^2 );

hold on; plot (x,f);
y = randn(1000,1) + 2;
x = -4:0.1:6;

n = hist(y,x);

bar (x,n);

MEAN = mean(y);
STD = sqrt(mean((y - MEAN).^2));

f = ( 1/(STD*sqrt(2*pi)) ) * exp(-0.5*((x-MEAN)/STD).^2 );
f = f*sum(n)/sum(f);

hold on; plot (x,f, 'r', 'LineWidth', 2);