Selecting Data for the Calculation
For a partial calculation, deactivate existing objects. Various tools, which may be combined, are available for this purpose which are described below.
Exclude Objects for the calculation
Objects can be included or excluded from the calculation by
- activating/deactivating individual objects via the ID on the object’s edit dialog (see manual "Introduction to CadnaA") or
- by using groups (see Groups) or
- by using variants (see Variants).
Deactivated objects are displayed by default with dashed lines. This can be changed on dialog Options|Appearance (see Object Appearance).
Calculation Area
By the object „Calculation Area“ an area can be defined being used for the grid calculation (see Receiver Grid). Several calculation areas can be defined in a project file. If no calculation area has been defined the entire limits are used when calculating the grid (see Limits).
Exclude Area
With the option „Exclude Area“ on dialog Calculation Area it is possible to exclude a calculation area laying inside the existing calculation area. Inside this area the grid is not calculated.
The calculation areas are evaluated according to their sequence in the object table from top to bottom. For each grid point, the state (exclusion yes/no) of the last calculation area in the object table containing the grid point is therefore relevant.
Note
For most use cases, it is therefore useful to order the table in a way that the exclusion grids are at the end of the object table.
Table Calculation Area
All calculation areas are listed on menu Tables|Other Objects|Calculation Area. The sequence of the data sets determines the sequence of calculation.
For these calculation areas, CadnaA will take into account all objects, even outside the calculation area, unless they are deactivated.