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Full Version: User interface like Time Value of Money in 48GX
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I have an application with several related equations and variables. I would like to write a program that behaves as the Time Value of Money does in the 48GX, allowing any of the variable to be solved if the others are known. Does anyone have or know of source code examples of that programming behavior?

I have used a custom MENU, as in the example on page 1-81 of the Advanced User's Reference; but, that does not have the variables on the screen that can be navigated to and all seen at the same time.

There's two different interfaces built-in to the 48gx for TVM. One uses the menu area to display the variable names (the standard "MSOLVR" functionality), and the other uses the full display with the "TIME VALUE OF MONEY" banner at the top.

Based on your description I'm thinking you are probably looking for the latter. If so, see the documentation for the INFORM command, which can get you pretty close to the same type of functionality. It's powerful, but requires setting up a large number of arguments on the stack prior to calling it. You may be able to find some examples of its use in comp.sys.hp48 newsgroup archives.

The built-in apps in the SOLVE menu are actually using an enhanced API that's only accessible with System RPL, so you may find that INFORM doesn't support some of the functionality that you're wanting to emulate. There's no easy approach to that type of situation, as it involves a fairly steep learning curve to follow that path. It's doable, but I wouldn't recommend starting down that path unless you have lots of time to devote to this.
There is a program to build such boxes here
And if you're looking for something to run on a GX, you could give my Input Form Builder (http://www.hpcalc.org/details/4211) a try:-)
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