You have a calculation running in a calculation field. There is no manual override.
Are there static conditions that define when ProductID = 12 or 6 but Quantity should not equal 1? These can be built into your calculation.
If there simply needs to be a manual override, then a strict calculation field is probably not the best thing to use here.
Can you flesh out your situation a little more?
AHUNTER3 on a different forum suggested the following and it worked.
Create an override quantity field.
Product ID ≥ 1 and Product ID ≤ 4; Length*Width;
Product ID = 5; Length+Width;
Product ID = 20; Length*Width;
Product ID = 12 or Product ID = 6; NewOverrideQuantityField; " ")
Thanks for your comments.
You can even set up a text field in a product look up table such as where you have the product's unit prices. You would store the calculation expressions for each product ID such as Length * Width for products 1 and 4 in this field.
Then you can define a matching text field, CalcExpression, that looks up this text just like a product description or price.
Your calculation would then look like this:
Evaluate ( CalcExpression )
This has the advantage of not needing to rewrite your case function every time you add a new product or change how an existing product is calculated. Such changes can then be made simply by editing records in your products table.
Thanks, I will definitely give that a try.