How to plot histogram?

Hello,

I have a code for plotting the signal like this :

samples=20;
mean_value=-4.2;
std_dev=2.3;
t=0:1:samples-1;
s=mean_value+std_dev*randn(1,samples);
plot(t,s);

and i want to create histogram, but i have error saying:"attempted to access hist(0)" or hist(-1). I have a code like this and I don't know what is the problem:

%histogram
nbins=10;
xmin=-15;
xmax=5;
hist=zeros(1,nbins);
w=(xmax-xmin)/nbins;
x=xmin+w:samples/nbins:xmax+w;
for i=1:length(s)
  if s(i)<= xmax && s(i)>= xmin
  idx=floor(s(i)-xmin/w)+1;
  hist(idx)=hist(idx)+1;
  end
end
bar(x,hist/trapz(x,hist));
hold on
x2=xmin:0.1:xmax-0.1;
y=normpdf(x2,mean_v,std_dev);
plot(x2,y);

I am pretty new at this and could use some help. Thank you.

Answer 1

[Steven Lord]

Why not just call the histogram function introduced in release R2014b?

[Uros Jankovic]

I just wanted to understand how does it work this way, and I will also gain some knowledge that I might need in future.

Answer 2

[Image Analyst]

hist() is an old deprecated function. Don't use it for the name of your variable.

Also you must make sure that idx never is 0 or negative or a non-integer floating point number.