Error in Spline (interpolation)

I am using interp1 to do a spline interpolation and I get the below output:

Warning: Matrix is close to singular or badly scaled. Results may be inaccurate. RCOND = 5.270915e-022. > In spline at 91 In interp1 at 279 ...and blah blah blah (more layers)

This is how I called it:

       for i = 1:length(fields)
       eval(['interpolated.', fields{i},' = interp1(choppedT1,chopped.',fields{i},',choppedMaster, ''spline'');']);
    end

"chopped" is a structure of vectrs that have been "chopped" to be the same length. choppedT1 is the timestamp vector for these vectors. choppedMaster is the timestamp vector I am interpolating to. Fields is the array of fieldnames (same for chopped and interpolated). I'm using eval like this because it allows for any fieldname to be used. any ideas?

Answer 1

[Bruno Luong]

The warning message issued possible due to there are abscissa (chopped filed) too close to each other. You could group them then average to a single data point before interpolation.

Note that structure fields can be accessed using dynamic fieldname, e.g.,

interpolated.(fields{i}) = ...

That syntax allows you to remove all the eye-hurting eval().