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Fill missing NaN values with Interpolation

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I have Matlab 2013, and I want to apply spline interpolation in my data matrix with NaN values. Is there any other method which can do this. As fillmissing functon is not available in lower versions.
  2 Comments
Tsehaye Gebreteklie
Tsehaye Gebreteklie on 19 Apr 2022
knnimpute is prefere than spline. you can write the code like this.
clear all;
clc;
Temp = xlsread(A);
Filldata=knnimpute(Temp);

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Accepted Answer

KSSV
KSSV on 12 Jul 2018
a = rand(100,1) ;
% put some NaN's
a(randsample(100,20)) = NaN ;
%%interpolate
x = 1:length(a) ;
a(isnan(a)) = interp1(x(~isnan(a)),a(~isnan(a)),x(isnan(a))) ;
plot(x,a,'.r')
hold on
plot(x,a,'b')
  1 Comment
EMMA POLLARD
EMMA POLLARD on 23 Feb 2021
@KSSV Is there a way to use the above method but omit larger gaps of data? For example if there is a string longer than 5NaN values could it avoid interpolating these sections?
Thanks

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More Answers (1)

ZaidiN
ZaidiN on 12 Jul 2018
Is this spline interpolation? Secondly this doesnt fill the locations of NaN with interpolated points.
  1 Comment
Pawan Sharma
Pawan Sharma on 12 May 2020
This is liner interpolation. To make it spline interpolation, add spine as a method of interpolation
a(isnan(a)) = interp1(x(~isnan(a)),a(~isnan(a)),x(isnan(a)), 'spline') ;
It do replace NaNs with interpolated values.

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