MATLAB: How to interpolate in 3d

Question

I have a matrix in 100 distane and 10 distance which i want to interpolate to 1

but as it is a matrix i want to interpolate in 3D

I have tried it interpolating in 2D and getting some irregularities in the which can be seen in attached picture

The 2D code is as follows

[num] = xlsread('Mappe2.xlsx') ;
n = 860;
num1=num(2:87,2:26)';
B = interp1(1:size(num1, 2), num1.', linspace(1, size(num1, 2), n));
n = 250;
B1 = interp1(1:size(B, 2), B.', linspace(1, size(B, 2), n));
surf(1:860,1:250,B1,'edgecolor','none');

How to code further to avoid these irregularities?

I have also attached the Excel file feom the code

Answer 1

You can use scatteredInterpolant to do this task. The following is an example.

% Read data file
Data = xlsread('Mappe2.xlsx') ;
% Adjust data to grid data format
x = Data(1,2:end);
y = Data(2:end,1);
[xGrid,yGrid] = meshgrid(x,y);
zGrid = Data(2:end,2:end);
% Apply scatteredInterpolant function
idx = isnan(zGrid(:));
F = scatteredInterpolant(xGrid(~idx),yGrid(~idx),zGrid(~idx),...
  'linear','linear');
% Interpolation (linear) and Extrapolation (linear)
zGridInterp = F(xGrid,yGrid);
% Show the result
figure
surf(xGrid,yGrid,zGridInterp,...
  'EdgeColor',  'none',...
  'FaceColor',  'interp')
view(2)
colorbar