Instantaneous recalculation

[Greg Fong]

I have a tabbed subform the second tab contains an embedded browse. The first tab contains invoice info as well as an invoice total field. The second tab contains line items as well as a field variable that calculate a total from the line items. I have a script that does a complex tax calculation that involves a number of IF statements. I want the results to be written immediately into the total field in the first tab as well as a field variable on the second tab. The user should be able to change the values in the line items and see the totals and the tax totals change. I am not sure where to put my tax calculation to achieve the same effect. Right now I have the tax calculation in the onchange tab event. I thought a button would work but the users are likely to forget to press it. Any suggestions?

[forskare]

RE: Instantaneous recalculation

Greg,

Why can't you use calculated fields? They will change instantaneously as you desire. I really don't think you need to use a variable.

kenn

[Greg Fong]

RE: Instantaneous recalculation

My calculations relate to sales taxes and require the calculation of up to three tiers of tax. Ordinarily you pay tax as a percent of the purchase price but some places have an additional layer of tax that is either a separate tax also based on the purchase price or it could be based on the sum of the purchase price and the first tax a sort of tax on tax. I have heard of jurisdictiopns that have a third layer!

I keep a table of tax structure that is linked to different jurisdictions around the world. Some places have one simple sales tax others have more than one layer some layers are tax on tax others are not. My routine uses the proper calculation for the proper city or state or country.

Anyway the IF statements in my routine take a basic purchase price and calculates the tax for each layer of tax depending on whether it is tax on tax or not. Then it adds all three layers to arrive at ther total tax. I don't know if it is possible to get this much code into a nested if statement. Is there a CASE type of structure that I could use in an expression?

[forskare]

RE: Instantaneous recalculation

Greg,

I see no reason why the if statements won't work in a calculated field. I have some calc fields with 3 if statements. You can have another calc field to simply show a total of however many other calc fields you want. I really don't see a problem. Give it a try. I think you'll be very pleased.

kenn

[whanigsberg]

RE: Instantaneous recalculation

Greg,

"Is there a CASE type of structure that I could use in an expression?"

Look up Select...Case in the Xbasic documentation. If you have lots of conditions this is much less of a headache than multiple nested ifs.

Bill

[forskare]

RE: Instantaneous recalculation

Greg,

I've studied your posts further and this is what I perceive you have:

Tab 1. Shows the customer name, address, etc. along with a field which shows the invoice total.

Tab 2. Shows line items along with a field which shows the total of the taxes and a field which shows the invoice total.

The best and easiest way to do this is based on your customer's needs. Will the customer want to see how much each tax is? I would because I want to see the exactly amount of each tax. An example of this is telephone billing. 1st, there is the federal tax, then the state tax and finally there may be a local tax. Each tax is shown separately so the customer knows exactly how much each tax is. (Required by law for phone billing)

Create a calculated field for the subtotal of the line items and then a calculated field for each tax and finally a field for invoice total. The invoice total field can simply be copied and pasted to tab 1.

Whenever a invoice item amount is edited, added or deleted, the amounts are instantaneously updated. No need for the use of a variable or multiple nested "if" statements.

You also might want to do a search on this board using "tax" and "Sullivan". You'll find an interesting tax question which may shed some light on your situation.

Hope this helps,

kenn