Grid Data Format
The grid data format can only be used for import of data.
The following table shows the format for results data stored as grid points and corresponding data values:
Table 9-3:  Grid, data
Section
Number of rows
Description
% Grid
1–3
x grid points separated by spaces
y grid points separated by spaces (optional)
z grid points separated by spaces (optional)
% Data
Number of y grid points (2D) or number of y grid points times number of z grid points (3)
Data values separated by spaces
Each row contains values for different x grid points for fixed values of  y and z. The rows first increase the  y grid value and then the z grid value. The grid points can also represent another independent variable that the data values depend on. For example, the “grid points” can be temperature values and the data values the thermal conductivity at these temperatures.
It is important to use a comment line starting with % to separate the grid points or other interpolation points and the data values that are associated with these coordinates or interpolation points.
It is possible to include more than one function in the file as long as a % Data header separates them one from the other.
In the COMSOL Multiphysics Reference Manual:
•
Interpolation
•
Examples of Spreadsheet, Sectionwise, and Grid File Formats
•
Exporting Data and Images
Rock Fracture Flow: Application Library path COMSOL_Multiphysics/Geophysics/rock_fracture_flow