Re: Access Excel formulae from an RPG

@Dave

You deserve credit for thinking outside the box. I probably never would have imagined using Excel to host web services. I shouldn't be surprised. Some people think they can download almost all their data and nearly run their businesses on Excel.

I don't know if Excel Web services are possible. And I doubt that it would be good at it, even if it were possible. I do understand that Excel is terrific at handling formulas. But in the case of insurance tariff calculations I don't understand how it would be more complicated in RPG.

I view tariff calculations as procedural intensive (step by step) as opposed to formula intensive (math). I view tariff calculations as applying weights and factors and percentages to data in records in procedural fashion. What am I missing? If it really is formula intensive, I'd still wonder how it would be more complex in RPG, which might reference SQL and other math functions.

We have procedures for calculating student grades. And I was surprised at the number of factors, weights, percentages, and steps involved in grade calculations. But the reason for coding them as procedures was so we could evoke them from a lot of different programs; which we do.

I don't see anything wrong with using Excel to double-check your RPG procedures. In fact I see good in that. But if you still think calculations should only be done in one place, I'd still recommend RPG at this point. If you were to go that route, then you might considering providing a browser base UI to your users that looked and behaved like a spreadsheet as opposed to 5250.

-Nathan.



----- Original Message -----
From: Dave <dfx1@xxxxxxxxxxxxxx>
To: RPG programming on the IBM i / System i <rpg400-l@xxxxxxxxxxxx>
Cc:
Sent: Thursday, March 15, 2012 3:19 PM
Subject: Access Excel formulae from an RPG

Hi all,

Today I was presented with the most complex set of mathematical
instructions in an rpg program I have ever seen. (insurance tariffs).
I was not involved in the development but as I was involved in other
tests on the product, that used these calculations, I was asked to
control the tariffs that were shown during the course of my own tests.
The user had supplied an Excel spreadsheet which we could use to enter
any test amounts to get the different details of the tariffs. So, to
test the rpg code, we are basically creating a client on a 5250 screen
and checking the displayed tariffs calculated by the rpg program with
those obtained with the spreadsheet. It doesn't seem right to me that
we have basically 2 copies of the formulas needed for the
calculations, the user's in the spreadsheet and ours in the rpg
program. The rpg code used to reproduce the excel formulae is very
complicated, and the programmer who wrote it is using the debugger to
be able to see the result of the different steps in the calculation!
How could the rpg program access directly the user's formulae? I
thought web service, but I would not really know where to start.
Thanks in advance for any suggestions.