Plot Normal/Gaussian distribution from set of data

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Hello All,
I want to plot a gaussian distribution of a set of data and see the mean and 3 sigma. I am using the below code but I am not getting the gaussian curve. Please help! Thanks!
x = [2.9954E-09,3.1314E-09,3.1155E-09,3.0940E-09,2.8861E-09,3.0875E-09,2.9685E-09,3.0532E-09,2.9003E-09,3.0931E-09];
[mu,s]=normfit(x,0,1);
%norm=normpdf(x,0,1);
figure; plot(x,norm);
figure; plot(x,norm);
  1 Comment
Kash022
Kash022 on 7 Apr 2016
I have managed to write this but can't calculate and plot mean and sigma.
x = [2.9954E-09 3.1314E-09 3.1155E-09 3.0940E-09 2.8861E-09 3.0875E-09 2.9685E-09 3.0532E-09 2.9003E-09 3.0931E-09];
norm=histfit(x,10,'normal');
plot(x,norm);

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Answers (1)

Image Analyst
Image Analyst on 7 Apr 2016
Try this:
x = [2.9954E-09 3.1314E-09 3.1155E-09 3.0940E-09 2.8861E-09 3.0875E-09 2.9685E-09 3.0532E-09 2.9003E-09 3.0931E-09];
norm=histfit(x,10,'normal')
[muHat, sigmaHat] = normfit(x);
% Plot bounds at +- 3 * sigma.
lowBound = muHat - 3 * sigmaHat;
highBound = muHat + 3 * sigmaHat;
yl = ylim;
line([lowBound, lowBound], yl, 'Color', [0, .6, 0], 'LineWidth', 3);
line([highBound, highBound], yl, 'Color', [0, .6, 0], 'LineWidth', 3);
line([muHat, muHat], yl, 'Color', [0, .6, 0], 'LineWidth', 3);
grid on;
% xFit = linspace(min(x), max(x), 100);
% yFit = max(x) * exp(-(xFit - muHat).^2/sigmaHat^2);
% figure;
% plot(xFit, yFit, 'r-', 'LineWidth', 2);
% grid on;
% Set up figure properties:
% Enlarge figure to full screen.
set(gcf, 'Units', 'Normalized', 'OuterPosition', [0 0 1 1]);
% Get rid of tool bar and pulldown menus that are along top of figure.
set(gcf, 'Toolbar', 'none', 'Menu', 'none');
% Give a name to the title bar.
set(gcf, 'Name', 'Line segmentation', 'NumberTitle', 'Off')
  1 Comment
Kash022
Kash022 on 7 Apr 2016
Thanks! It works. Is there a way where I can show on the plot the mean and the 3 sigma?like an arrow showing the extent of the sigma?

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