14.2.4 Gridding of Sparse or Missing Data

The Sparse XYZ worksheet to matrix conversion is similar to the Regular XYZ conversion mentioned earlier in this section (i.e. X and Y data values must be regularly spaced), except that in the case of the Sparse conversion, missing XY pairs are acceptable. In the following example, worksheet data are treated as though X and Y values are linearly spaced (X increasing by 5 and Y values increasing by 2), excepting for missing triplets at (10,6), (10,8), (15,4), (15,6), (20,4), (20,6), (20,8), (25,4), (25,6), (25,8), (30,4) and (30,8).

Gridding of Sparse or Missing Data 01.png Gridding of Sparse or Missing Data 02.png

With conversion, Origin generates the following matrix:

Gridding of Sparse or Missing Data 03.png

So, using the Sparse matrix conversion method, you can create a 3D plot with Z values plotted only at selected XY values, as in the following 3D bar plot:

Gridding of Sparse or Missing Data 04.png