Hi @John-TT,
Thanks for providing your use case! I can show you an example of calculating sums from user input
I created an app with an order screen that allows a user to add items and a specified quantity to an order, and the total bill is calculated on the screen.
First, I created a table of items and specified a cost for each item:
I have another table where I store OrderEntries. You can see the columns I added and that the Item column is formatted as a rowlink to the Items table:
And in this table, the Cost column is formatting to calculate cost of the item multiplied by the quantity. The cost is retrieved from the rowlink of the item in the Item column. So for my example, the formula in the cost column is: =[Item][Cost]*[Quantity]
And I have third table set up that stores the order total, once submitted. So these are the columns that I've added:
For the app, this is what the screen looks like:
And this is how I set it up:
The screen has a form where the user can select an item to add to an order and specify a quantity. Both fields are editable to allow user input. The quantity field is a set to a number format, and the item field is a rowlink format to the items table:
When a user clicks on the "Add to Order" button, it will write a new row to the OrderEntries table. This writes the order number on the screen, item selected, and specified quantity. (The calculation of that cost happens in the table, as shown in the table set up above):
Below that form, I added a list that is filtered to display only the entries of the order on the screen. So it's a column list of the OrderEntries table, and the filter formula I used in my example is: =Filter(OrderEntries,"OrderEntries[Order]=%",$[Order])
At the top of the screen, I have a field that calculates and displays the total of all of the entries for that order. This is achieved with a SUM() function wrapping a FILTER() of the cost for each entry for the order on the screen.
For my example, the formula looks like: =SUM(FILTER(OrderEntries,"OrderEntries[Order]=%",$[Order])[Cost])
And finally, I have a "Submit Order" button that will submit the calculated total, order number, and customer name to the OrderSummaries table:
And this is what it looks like in the OrderSummaries table once submitted:
I hope this helps! As shown in this example, you can do calculations of values both in the Tables and in the app through Builder.
Let me know if you have any questions on this.