I have an incomplete and buggy application to convert expresions from normal (infix) notation to reverse polish notation (RPN) needed for XML gauges. As an example, it converts:if{ ( A > B ) && ( C < D ) } ( X + 2 * Y ) toA B > C D :(becomes a b maxEDITIt also replaces '>' with '& gt ;', '<' with '& lt ;', and '&' with '& amp ;' (without the spaces) but the forum changes them back!

Yep .. Both correct ..Cheers, Rob

Great interest here, I just can't get my head to think in RPN, particularly when it gets messy and complex. In a way you are thinking about a kind of compiler :)

I've tidied it up and will be happy to email it to 2 or 3 people for comment before deciding whether to upload it to the library.First come, first served!

As I believe the testing should be done by XML gauge programming cracks that "live" RPN to be able to correctly judge the results other than "does the gauge show up and work as expected in FS2004?" I will for the time being wait for the downloadable version. Just please let us know when that will be :)

Would any of the HP calculators work? LOLRPN'ing since 1975!Algebric gives me the shivers!W. Sieffert

I doubt it. Calculators go one step further and evaluate the expression numerically. Anyway the Microsoft requirements aren't strictly RPN .The way in which a value is assigned to a variable: 1 > Ai.e. assign 1 to A is still infix. The RPN equivalent should be:1 A >