extrapolation of contour data set

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Hello everyone!
I have made a contour from my data (both is attached), but I need have data in contour that is from 0 to 0,1.
I tried to increase the size of the matrix by giving smaller increment to the variable but even 1000x1000 matrix gave the same contour.
If you know the solution, please share. Thanks

Accepted Answer

Bjorn Gustavsson
Bjorn Gustavsson on 6 May 2022
Since the minimum value of your counttest-variable is 0.0853 or thereabouts you will never get any contour for levels lower than that. You can make contours at arbitrary levels of your choise:
contour(counttest,[0:0.001:0.1,0.2:0.1:1]) % or whatever levels you so desire in the range of the data
HTH
  2 Comments
Asliddin Komilov
Asliddin Komilov on 6 May 2022
cannot extrapolate/interpolate the data towards zero?
Bjorn Gustavsson
Bjorn Gustavsson on 6 May 2022
You should always look at your data first. Try:
plot(counttest)
and you will see that you have a rather broad minima in your 2-D data. Any interpolation will lead to additional points inbetween the values around your interpolation-points. If you were to extrapolate outside the edges of your data the "sensible" (in the extent that can be applied to extrapolation) extrapolations would lead to increasing values - since both gradient and second derivatives are positive. Therefore your data will have a minimum at around 0.0853. If you expect to get some response at below that you will have to do something completely different.

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