Column tops
This function writes the coordinates of the `top' of each column in a block model to a string file. The `top' of a column is defined as the first block encountered when moving through the column in a given direction.
This function is very useful when using the -Z direction to create DTMs of the upper or lower surface of a constrained model.
To run this function: Choose Block model > Column processing > Column tops, or...
Direction of column
Select the direction that defines the top of a column. The directions which may be used include:
- -X, The columns are horizontal and aligned with the X axis of the block model and are processed in order of maximum X to minimum X value.
- X, The columns are horizontal and aligned with the X axis of the block model and are processed in order of minimum X to maximum X value.
- -Y, The columns are horizontal and aligned with the block model Y axis and are processed in order of maximum Y to minimum Y value.
- Y, The columns are horizontal and aligned with the block model Y axis and are processed in order of minimum Y to maximum Y value.
- -Z, The columns are vertical and are processed in order of maximum Z to minimum Z value.
- Z, The columns are vertical and are processed in order of minimum Z to maximum Z value.
Nominal value above top
Column Tops is generally used on constrained models. The entered value will be assigned to the appropriate coordinate (X, Y or Z) for columns that exist in the model but not in the constraint.
Location, Id
Supply the Location and Id of the string file to which the tops of columns will be written. Each point in the string file will be the (y, x, z) coordinate of the centre of the `top' face of the `top' block.
Constrain report
Select `Yes' if you wish to constrain the blocks.
Choose Apply to extract the column tops or Cancel to return to the BLOCK MODELLING menu.
Result
The tops of columns will be written as points in String 1 in the nominated string file.