Define Grid
This function allows you to create a grid file by specifying X and Y coordinate ranges and the point interval for each direction. A grid file will be created in which you may enter a Z value for each point in the grid and, optionally, one or more descriptions for each point.
To run this function: Choose File tools > Grid tools > Define new grid, or...
Grid name
The grid being defined must be given a name. The grid is stored as a file with this name, and a `.grd' file extension.
X and Y, Step size, Minimum and Maximum
The size of the grid is defined by six inputs which are:
| Y step size | The distance between grid nodes in the Y direction. |
| Y minimum | The starting Y value for the grid. |
| Y maximum | The ending Y value for the grid. |
| X step size | The distance between grid nodes in the X direction. |
| X minimum | The starting X value for the grid. |
| X maximum | The ending X value for the grid. |
Number of nodes in grid
The number of nodes which will be in the grid when it is created is displayed.
Length of description field and Number of description fields
If description fields are required in the grid then the length of the description field (the maximum number of characters) and the number of subfields (D1, D2, etc.) must be defined. If description fields are not required then simply leave the number of description fields set to 0. The maximum number of sub fields (D1, D2, etc.) is 100 with total characters for all descriptor fields being 512.
Initialize option for Z values
This allows you to define how the initial values for the grid nodes will be assigned. The three options available are:
- Null, If the initialise option of Null values is selected, the grid will be created with the Z values set to NULL and the description fields set to spaces.
- Random, If the initialise option of Random values is selected, the grid nodes will be created with random values which fall between the entered minimum and maximum bounds.
- Fixed, If the initialise option of Fixed values is selected then a fixed value for the Z field must be entered.
Minimum Z value for grid
Enter the minimum Z value for grid. This field is active only if you had selected "Random" values as the Initialise option for Z values.
Maximum Z value for grid
Enter the maximum Z value for grid. This field is active only if you had selected "Random" values as the Initialise option for Z values.
Define fixed Z value for grid
Enter a fixed value for the Z field. This field is active only if you had selected "Fixed" values as the Initialise option for Z values.
Define initial values for description fields
Values
Enter the initial values required for each description field which will exist in the grid.
Result
After successful completion of all these steps the grid file will be created.