How can I get a smoothing line like Excel?

Dear all,

I got some test data sets and ploted them in excel, the following image is the result.

Left : no smoothing, just connecting each data with direct lines.

Right : connecting each data with default Excel smoothing method.

Excel smoothing method works well.

But I tried some Matlab methods such as interp1, it seemed that they cannot work normally in my data sets.

In my opinion, the reason is that both x value and y value are not monotonous.

So are there any methods provided by Matlab library that can solve this problem?

Or any advice about what method Excel is using to plot a smoothing curve.

Best regards,

Sam

Answer 1

[Nora Khaled]

I tried the answer to this question

https://www.mathworks.com/matlabcentral/answers/411231-connecting-data-points-in-a-smooth-curve

with your data

x = [-1 -.6 0 .6 1 .6 0 -.6];
y = [-0 .6 1 .6 0 -.6 -1 -.6];

I think it works...

[Sam Cao]

Thank you very much.