What is difference between fit and fitlm function in MATLAB?

I am trying to fit the data between two variable i.e., x and y. For fitting the data I am using fit and fitlm function.Upto the polynomial order 2 (poly2) I am geeting the same coefficient value from both function but while using the higher order polynomial greater than 2 I am geeting NaN value from fitlm function and some value from fit function. What is the reason behind this?

I have attached the screenshot of difference between two function and also the excel sheet that includes my data.

Answer 1

[Sam Chak]

@Meghraj Kc

You read about the differences between fit and fitlm here:

https://www.mathworks.com/help/stats/lime.fit.html

https://www.mathworks.com/help/stats/fitlm.html