Mapinfo GIS tutorial – How to Create Gridded surface using Encom Discover 9.0 #2

The Gridding Tool consists of a series of tab dialogs for grid parameter set-up that create a surface grid. Accompanying each dialog box is a preview window of the grid as it is created.

On the Input tab of the Gridding dialog, select Elevation from the list of available fields to grid. The image appears on the right hand side of the dialog. Above the grid preview are 6 buttons and a pull-down list. These buttons control the display properties of the grid in the Preview window. Ensure that the Apply histogram equalisation button is selected and select pseudocolor from the drop down list of colour tables.
Right-mouse click in the Preview window to display the pop-up menu:

On the Method tab, set the Method to Triangulation. The gridding methods provided use different algorithms in order to interpolate values for grid cells from and between the input data points. Triangulation uses the Delaunay triangulation method which creates triangles between all the data points. Grid cell values are then assigned based on the coplanar values of the triangle in which each grid cell is located. This gridding method is best suited to datasets which need to honour the original data input points as accurately as possible: e.g. elevation data.
Other types of datasets such as geochemical data can be gridded using different interpolation methods such as Minimum Curvature or Inverse Distance Weighting.
The Grid Geometry tab specifies the grid cell size which may be altered manually if required. The extents of the data to be gridded can also be altered under the Data Coverage options.
On the Output tab save the grid in a Geosoft format [.GRD] named TOPO_GRID.TAB. Click the OK button and Discover will save the grid and open it up into a new map window or the map window containing the SPOT HEIGHTS data.

Continue to tutorial No. 3