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Extrpoolation not along dimension

Asked by Rafael Kübler on 9 Nov 2017
Latest activity Commented on by Torsten
on 9 Nov 2017
Hello together,
i have a following simplyfied matrix z with corresponding x and y axis
z = [3 2 1 1 1 1 1 1; ...
2 3 2 1 1 1 1 1; ...
1 2 3 2 1 1 1 1; ...
1 1 2 3 2 1 1 1; ...
1 1 1 2 3 2 1 1];
x = 1:8;
y = 1:5;
now i want to extrapolate z to the y axis of
yNew = 1:6;
the extrapolated row in z should obviously shold look like this
zNew1(6,:) = [1 1 1 1 2 3 2 1]
and not like
zNew2(6,:) = [1 1 0 1 4 3 1 1]
zNew2 would be the result of an linear extrapolation along the dimension of y.
But obviously the data in z should look extrapolated like zNew1 which would be a diagonal extrapolation.
How can i extrapolate data which is not as simple as this example?
thank you for your help.
Rafael

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1 Answer

Answer by Torsten
on 9 Nov 2017
 Accepted Answer

There is no "obvious" way to extrapolate data - that's why several methods exist to do so.
There is no other way than just specifying a formula. This formula can of course be as complicated as you like - including intelligent algorithms that analyse the structure of your data matrix.
Best wishes
Torsten.

  2 Comments

What are those "several methods"?
Torsten
on 9 Nov 2017
Some ways to extrapolate:
- constant extrapolation
- linear extrapolation
- nearest neighbour extrapolation
- quadratic extrapolation
...
See also
https://de.mathworks.com/help/matlab/ref/interp1.html
under the "extrapolation" section.
Best wishes
Torsten.

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