====== Calculate function   ======

 


 
==== Description ====
 
Returns the result of evaluating a dictionary item.
 
==== Syntax ====
 
//value// = **Calculate**(//expression//)
 
==== Remarks ====
 
You can use the Calculate function in place of the {} (Braces) function. Calculate must be used if the column name is not known at compilation time. The expression specified in the Calculate function must evaluate to a column name in the file that has been opened to the system variable @DICT.
 
==== See Also ====
 
[[Braces_operator|{ } (the Braces operator)]]
 
==== Example ====
 
<code>
The following example shows how to evaluate column values by reference to the dictionary column name.

/* The following code fragment opens the SAMPLE_PRODUCTS table then the dictionary for that table, then reads the desired row, using @ID, then calculates the desired column value, using the dictionary column name. It returns the price of the specified item. */
table = "SAMPLE_PRODUCTS"
key = "TCHBUL"    ;* the technical bulletins product
Value = ""    ;* initialize the return variable
@ID = key
Open table To tablevar Then
  Open "DICT. ":table To @DICT Then
    Read @RECORD From tablevar, @ID Then
      dict_field = "INV_AMT"
      * The following three code segments are equivalent:
      Value = {INV_AMT}
      Value = Calculate("INV_AMT")
      Value = Calculate(dict_field)
    End Else
      status = Set_FSError()
    End ;* Read
  End Else
    status = Set_FSError()
  End ;* Open dictionary
End Else
  status = Set_FSError()
End ;* Open table

/* Notice that in each case, the dictionary item INV_AMT is calculated. */
</code>