If I understand your question correctly then follow these steps:
1. Create one variable and write Allocation field expression on that (which you wrote in straight table).
2. Add input box object and set created variable on it.
3. Now whenever you change your filter, input value will also change as expression value.
Hope this will help you
Please find the attached application.I used a input filed to enter the values inside a straight table and calculate based on the inputs.
Please let me know if you need any additional details.
Test.qvw 149.8 K
Sorry for replying so late, I was on a vacation. Please find below the script and expression.
LOAD Produc_Name,1 as Test,Product_Values
(ooxml, embedded labels, table is Sheet1);
Dimension is Data.Product_Name and expression is InputSum(Data.Test)
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