MATLAB: How to populate 2D array from 2 vectors perpendicular to each other

MATLABvectors to array

I have 2 files. Each file contains 4 columns. Column 1, 2 and 3 define the location of a point in x, y, and z-axis respectively, on a Cartesan coordinate. Column 4 is the Value of that point. 'Inline' and 'Crossline' are perpendicular to each other and intersect at (0,0) coordinate. How do I populate a 2D array from these 2 files? (The data below are simplified. The real data has finer resolution)
Inline =
   2.800000            0   15.0000    1.3678
   1.000000            0   15.0000    1.2000
          0            0   15.0000    1.0000
  -1.000000            0   15.0000    1.2000
  -2.500000            0   15.0000    1.5688
Crossline =
          0    -2.300000   15.0000    1.3546
          0    -1.000000   15.0000    1.1000
          0            0   15.0000    1.0000
          0     1.000000   15.0000    1.1500
          0     2.700000   15.0000    1.3558

Best Answer

This is my attempt to generalize your description. Let (x0,y0,z0) be the point of intersection of your two lines. (Note: The lines you gave intersected at (0,0,15).) I have abbreviated the names of the lines as 'I' and 'C'.
 [XI,XC] = ndgrid(I(:,1),C(:,1));
 [YI,YC] = ndgrid(I(:,2),C(:,2));
 [ZI,ZC] = ndgrid(I(:,3),C(:,3));
 [VI,VC] = ndgrid(I(:,4),C(:,4));
 OUT = [XI(:)+XC(:)-x0,YI(:)+YC(:)-y0),ZI(:)+ZC(:)-z0,VI(:).*VC(:)];
I depended entirely on your stated expected output, since I could not understand your verbal description of it at all. I gather you want to complete the "grid" consisting of all possible pairing of points on the two lines and at each grid point you want the value to be the product of the corresponding values given by the two lines.
Roger Stafford
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