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Interpolation The coordinates do not lie on a structured tensor product grid


I have a big array of multidimentional data 50 Mb, 500 000 elements. and I want to interpolate it and make a normal function.


Please do not mark this question as a duplicate straightaway, because I read many answers and they actually do not answer my question, they are a little bit different. I do not ask how to fix this problem, but more about definition and a way to find where my data is wrong.


Data example is this:


{
  {{-0.5, -0.4898989898989899, 1., 0., 0.1}, 0.10120921662021362},
  {{-0.5, -0.4898989898989899, 1., 0.12566370614359174, 0.1}, 0.1012092163684851},
  {{-0.5, -0.4898989898989899, 1., 0.25132741228718347, 0.1}, 0.10120921611675658},
  {{-0.5, -0.4898989898989899, 1., 0.37699111843077515, 0.1}, 0.10120921586502805},

  {{-0.5, -0.4898989898989899, 1., 0.5026548245743669, 0.1}, 0.10120921561329953},
  {{-0.5, -0.4898989898989899, 1., 0.6283185307179586, 0.1}, 0.101209215361571}
}

This small example works fine, but when I try to interpolate all my data, I get this error


Interpolation::indim: The coordinates do not lie on a structured tensor product grid.


My questions are:




  1. What is "structured tensor product grid"? Can someone give me example of "structured tensor product grid" and "NOT structured tensor product grid"? Might be I will be able to change my data accordingly, but I could not find definition of this term anywhere.





  2. Is there any way to find in my big data list (50 Mb) this place, where deviation (something wrong) happens? In other words how to find where my data is wrong?






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