Interpolation of zero values ​​in matlab

Hello! The readings from the gas sensor look like this: 70 71 0 69 0, at a temperature of 12 12.2 12.1 11.9 11.2. I try to interpolate all zero values, but for some reason I don’t consider it at all

[cat,nocat]=min(Animals);  %readings from a 1x1200 thermometer
  [dog,nodog]=max(Animals);  % gas sensor reading 1x1200
  for i=1:length(cat)
  if dog(i)<0  % if some indication is less than 0 (they are all positive)
  interpol(i)=dog(i);  % the location of these zeros and this is what we interpolate (1 and the last value are not zero)
        c(i)=interp1(interpol(i),cat(i),nearest);  % interpolate;
  else(i) dog(i)>0  % if the values ​​are greater than 0
  c(i)= dog(i);  % That testimony and remain
  end   
  end

Answer 1

[Alex Mcaulley]

Try this: (Note that "cat" is not a good variable name because it is a Matlab function)

[cat,nocat]=min(Animals);  %readings from a 1x1200 thermometer
[dog,nodog]=max(Animals);  % gas sensor reading 1x1200
vq = interp1(cat(dog>0),dog(dog>0),cat(dog<=0),'nearest','extrap'); %nearest or other interpolation method you want
dog(dog<=0) = vq;

[Lev Mihailov]

Error The grid vectors must contain unique points.

[Alex Mcaulley]

If you use the sample you provided it works. The error is due to have repeated points (points with the same temperature in your case). See this reference to see what is happening and how to fix it.

[Lev Mihailov]

[cat, dog] = unique(cat); 
vq = interp1(cat(dog>0),dog(dog>0),cat(dog<=0),'nearest','extrap'); %nearest or other interpolation method you want
dog(dog<=0) = vq;

I did this and now vq in workspace is displayed as [] 1x0

And I do not like the values ​​of cats and dogs (they greatly decreased was 1200 and it became 1x732)

[Alex Mcaulley]

Try with this:

[cat,nocat]=min(Animals);  %readings from a 1x1200 thermometer
[dog,nodog]=max(Animals);  % gas sensor reading 1x1200

[newCat, index] = unique(cat);
newDog = dog(index);
vq = interp1(newCat(newDog>0),newDog(newDog>0),cat(dog<=0),'nearest','extrap'); %nearest or other interpolation method you want
dog(dog<=0) = vq;

[Lev Mihailov]

Thank you, everything seems to work, but now I have 202 values. And I just wanted to replace my zeros in the dog with the values ​​of this interpolation, that would be 1x1200, all values ​​are positive numbers

[Alex Mcaulley]

What variable has 202 values? vq? That is right (it is the number of zeros in dog variable)

If you see the dog variable it should have the same number of elements than in the begining (1200) with non zero values.