Try something like this —
%Import front sonar for 30cm:
sonar_F_030 = readtable('https://www.mathworks.com/matlabcentral/answers/uploaded_files/1195733/sonar_F_030.csv')
%Split ranges from file
range = sonar_F_030.range;
pd = fitdist(range,'Normal');
mu1 = pd.mu;
sigma1 = pd.sigma;
% x = (-3:0.01:3);
x = linspace(min(range), max(range)+0.01, numel(range));
y = normpdf(x,mu1,sigma1);
figure
plot(x,y)
grid
Make appropriate changes to get the desired result.
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