how to interpolate nx2 (x,y) matrix include some NaNs with newton's interpolation.

Question

Dessa 2020-6-23

回答： Ameer Hamza 2020-6-23

% data1 is loaded data, nx2 matrix
x1 = data1(:,1); % constant time interval, nx1 matrix
y1 = data1(:,2); % data about x, nx1 matrix 

x1, y1 is like

x1 = [ 0 5 10 15 20 25 30 35 40 45. . . ]

y1 = [ 0 0 2 3 NaN 11 14 17 NaN 13 . . . ]

how can i interpolate data1 to idata1 with newton's interpolataion (or other interpolation without using interp1).

idata1 is nx2 matrix with all NaNs are replaced by interpolation result.

Answer 1

Ameer Hamza 2020-6-23

Since all points in x1 are equidistant, therefore, it is not really relevant in the interpolation. You can use fillmissing(): https://www.mathworks.com/help/releases/R2020a/matlab/ref/fillmissing.html to replace the NaN values. It gives several different options to replace the missing values.