This tip covers the use of the instruction model: ZERO(NUM). When is a number not a number? When it has no value. That doesn’t present an issue unless you start running calculations based on an unanswered number. The solution is ZERO(NUM).
What ZERO expression does is return the number value (if there is a number) or zero.
Use for a sum of different number variables
SET Fruit Total NU TO ZERO(Apples CNT) + ZERO(Oranges CNT) + ZERO(Tangerines CNT)
Use to provide a Total off a Repeat
REPEAT Inventory RPT
SET RESULT TO RESULT + ( ZERO(Item CNT) * ZERO(Item Price NU) )