c# - How to replicate what Excel does to plot a Scatter with

I need to replicate an Excel "Scatter with Smooth Lines" graph in code. I'm trying to use a line with Highcharts, so I'm must get the data that Excel uses to build the smooth line. This is Excel

Present your data in a scatter chart or a line chart - Microsoft Support

How to Plot Bivariate Data in Excel? - GeeksforGeeks

Is it possible to generate a scatterplot with all data and then have the user be able to highlight subsets of data using dropdown lists in MS Excel? - Quora

Scatter Plot for Multiple Data Sets in Excel, Scatter Plot Graph

How to make a scatter plot in Excel

How to Make a Scatter Plot in Excel to Present Your Data

Help Online - Quick Help - FAQ-621 How can I put a straight line to a graph at specified X or Y value?

how to make a scatter plot in Excel — storytelling with data

Scatter Plot in Excel (In Easy Steps)

c# - How to replicate what Excel does to plot a Scatter with smooth lines graph - Stack Overflow

Making Scatter Plots/Trendlines in Excel