Pitney Bowes MapInfo Vertical Mapper - Manual (Page 83)

Chapter 5: Creating Grids Using Other Methods
User Guide
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6. In the Enter Data Description box, assign an annotation (maximum 31 characters) that will be
carried as a header in the grid file.
7. In the Output Grid Name box, type a new file name or accept the default.
8. Click the Finish button.
Exploring the Grid Buffer Dialog Boxes
The Source Table list enables you to choose from tables available for processing.
The Use Nodes Only option enables you to create points from the existing nodes along the
polylines.
The Maximum Distance option enables you to add extra points along polylines ensuring that no two
points are farther apart than the Distance value.
The Distance box enables you to enter the maximum distance between points.
The Cell Size box enables you to define the cell size in the native coordinate system units of the
table. The grid dimension (in cell units) varies inversely with cell size: the smaller the cell, the larger
the grid file. The value you choose should be a compromise between the degree of resolution
required for analysis and visualization purposes, the processing time, and the file size. The units are
displayed next to the boxes. If the source polyline file is in a latitude/longitude projection, the units of
the radius value are displayed. Otherwise, the units are those of the table’s coordinate system.
The Buffer Distance box enables you to define the maximum size, in radius units, of a circular zone
centred on each grid node. For each point lying within this search zone, the distance between the
grid cell (the centre of the zone) and the point is measured. The value of the grid cell will be the
distance to the closest point. If no point is within the search radius, the cell will be assigned a null
value.