how to plot a histogram with distribution fitting?

I want to plot a histogram with distribution fit.

I use this code:

 z=[1,2,3,4,5];
l = [ 502 3341; 724 3502; 1310 3379; 2966 4001; 1915 3858];
figure;bar(l,'stacked')
set(gca,'xticklabel',z);

to plot a stacked fig.

but now I want to plot a histogram fig with distribution fit, - with my data - like this:

I use:

 hist

but it didn't work ): , giving me an error "double"

how I can do this ?

[Star Strider]

You’re probably looking for is histfit function. This is likely an ‘xor’ situation, where you can fit ‘battery’ or ‘battery-related’ but not both at the same time.

Feel free to experiment. It’s highly unlikely, but I could be wrong!

[Amr Hashem]

I try:

 z=[1,2,3,4,5];
l = [ 3843; 4226; 4689; 6967; 5773];
figure;histfit(l)
set(gca,'xticklabel',z);

it produce this shape:

which not what i want...!

[Image Analyst]

Why are your counts and categories, and even the size of the dimensions of the badly-named "l" different all the time? I'm not even clear what you want. I see a Gaussian curve over a bar chart in both cases. What do you want? Do you want the bar stacked like when you used a 2D l instead of a 1-d l?

[Amr Hashem]

sorry for the badly name "l" , I'll change it.

first "l" s is a stacked so [ 502 3341 ;... ], is equal to

second "l" s [ 3843;...].

and I want to plot a histogram and then draw over it a distribution fit curve.

like this but on my data:

or this

I try many functions:

 hist
histogram
histfit
histc

but it didn't work, any idea please?

Answer 1

[Image Analyst]

If you have no particular shape in mind, like the last plot above that you showed with the lumpy red curve, then you can use a Savitzky-Golay filter (demo attached). Attach the data for your last bar chart and I'll show you how with your actual data.

Answer 2

[Image Analyst]

Alright, I did a full blown demo for you. I let you choose an image to read in, then get the histogram, then smooth the histogram with a Savitzky-Golay filter (which is like a sliding polynomial filter). See the attached code below this image that it creates:

[Amr Hashem]

it seems that the image is not well attached

[Zhang zhengnan]

Thank you for your answer.Can you attach code about 'smooth the histogram with a Savitzky-Golay filter'?