Addition Parameters

Use this column to enter a variable name for the block model that will be created by the addition of the other two. The variable name, which can contain a maximum of 30 alphanumeric characters, must start with a letter. Block model variables that will be used for export to Isis databases should not have a name exceeding 5 alphanumeric characters.

Enter an optional 40 alphanumeric character description of the variable.

Enter the default value. The following characters may be used in combination with the default value, but not on their own:

[ ] ( ) { } %, + - * / &

Note:   We recommend that the default value is not a true value, that is, the default value does not occur in the block model. The reason for this is that in reserves reporting, default values are reported as an "unknown" category. For example, if you assign 2.8 as the default value for SG, and 2.8 happens to also be the global block SG value, then the reserves calculation will report the "true" 2.8 values in the wrong category (the "unknown" category). It is therefore better to use a non true default value such as -99 and then run a script to re-assign all blocks to 2.8. This way the blocks with SG = 2.8 will be reported in their correct category.

Important:  Byte and short data types must not have a negative default value because they are unassigned.

• Name - This is used for character type data. It is only possible to add one character type variable at a time. The description is entered in the Description field.

• Byte - <Integer * 1 > - This uses a single byte of memory. Using byte data type saves significant memory particularly if you have a rock code that is an integer in the range 0 to 255.

• Short <Integer * 2 > - This is a short integer taking two bytes of memory in the range -32767 to +32767.

• Integer <Integer * 4 > - This is a fixed point number (-2,147,483,648 to +2,147,483,647).

• Float - <Real * 4 > - This is a real number. It is generally used for single precision numerical data codes such as grades and densities - up to seven significant figures.

• Double - <Real * 8 > - This requires two consecutive storage units providing greater precision than real number types and is used for numbers up to 14 significant figures.

Note:   Variables to be used as the estimated grade in grade estimation must be of a float or double data type.

The following options relate to how the variables are to be merged. Only one method can be chosen.

• Assign Default Value - Select this option to assign the default value to the block.

• Dominance - Select this option to use the values of the first and second model variables for the variable of the new model. Refer to figures 5 and 6 for a graphical example: Select, from the drop-down lists, the variables. In the lists, the block model name precedes the variable name.

  

  Figure 1 : Model 1/2 Values

  Check whether the variable from first or second model takes preference for the overlapping area.

  

  Figure 2 : Overlapping Area Values

• Average of variables - Select this option to use the average values of the first and second model variable for the variable of the final model. Averaging variables does not apply to name variables.
  

  Example:  Using figure 5 as an example, the average value for the first cell would be 0.55 (0.6 if rounded), that is, value in the first model is 0.1 and in the second 1.0. Select, from the drop-down lists, the variables from which to calculate the average. In the lists, the block model name precedes the variable name.

• Sum - Select this option to sum the values of a variable from the first and second model and see the resulting value in the resultant model.

• First minus second - Select this option to subtract the value of a variable in the second model from the value of a variable in the first model and see the resulting value in the resultant model.

• Direct mapping - Select this option to use variable values of one model only. Select, from the drop-down list, the variable. In the list, the block model name precedes the variable name.

• Use Scripting File - Select this option to use an existing script file for the variables of the final model. The drop-down list contains <proj><var>.bcf and <proj><name>.bcf script files. Click Browse to select a file from another location.

  The first type is generated automatically through the Variable dominance, Average of variables, and Direct variable mapping options on this panel.

  The second type is created through the Manipulation > Edit Script option. The <proj><var>.bdf file is a simple script file. It contains the variables and a default value that is used for the new model if no values exist.

  Automatically Generated Script File

  IF (m1:material ne "-99999999")
  THEN 
      m3:mineralisation = m1:material
  ELSE
      m3:minieralisation = "waste"
  ENDIF
  END

  where :

  m1 is the first model (there is only one model as the file was created as a result of selecting the Direct Mapping Variable option)

  m3 is the final model. For more complex conditions, use the Manipulation > Edit Script option.

  Variables in the second model are skipped if they are identical to a variable in the first model.

Select the input variable from the first of the two block models used to perform the addition.

Select the input variable from the second of the two block models used to perform the addition.

Note:  This option is available only if you have selected Direct Mapping in the Generate Output Value Method column.

After clicking the button, use the drop-down list to select the dominance order of the variables. In the list, the block model name precedes the variable name.