Well, I have 3 stored values: store_value_1, store_value_2 and store_value_3.
I need to check whether are store_value_1 + store_value_2 = store_value_3. What Action and Function should I use to calculate that? I've tried with Action "Check string values" (because stored values are decimal). For "Parameter Value 1" I would like to use function such as ?add($store_value_1, $store_value_2), "Action Type" is equals, and "Parameter Value 2" is store_value_3. But that doesn't work...
Without knowing what doesn't work (or what you expect versus what you receive), it's hard to give a concrete answer. Nevertheless, here's a few pointers:
- Read the documentation on the predefined functions. It explains which format the functions are calculated / processed in
- Bear in mind you may need to use the functions trunc or round to get the numbers you need
- If you're having trouble with more complex functions, then break each part of the function down and check your interim results e.g. by entering the interim value via replace text into a text field. That should help you see where you're going wrong.