I've gotten a simple string case evaluation to work, but when I try any kind of arithmatic it just evaluates to 0:

This works:<String>Fuel Burn: %((A:NUMBER OF ENGINES, NUMBER))%{case}%{:4}%((A:Eng4 fuel flow GPH,gallons per hour))%{:1}%((A:Eng1 fuel flow GPH,gallons per hour))%{end}%!4.0d</String>This Doesn't:<String>Fuel Burn: %((A:NUMBER OF ENGINES, NUMBER))%{case}%{:4}%((A:Eng4 fuel flow GPH,gallons per hour)4*)%{:1}%((A:Eng1 fuel flow GPH,gallons per hour))%{end}%!4.0d</String>

Note the only difference is that I've tried to multiply Eng4 fuel flow by 4Any suggestions?Thank youPaul

Hi,Try:%((A:Eng4 fuel flow GPH,gallons per hour) 4 *)% May be there were some spaces missing?Jan

That did it; thanks! Are there some rules posted in the SDK or anywhere else as to where spaces are needed in an evaluation?

That did it; thanks! Are there some rules posted in the SDK or anywhere else as to where spaces are needed in an evaluation?

None that I've ever found... However, if you think about it a bit, it's really common sense to use spaces to separate words, operators, and numbers in a sentence; which is all XML script is anyway! :( Imeanhowhardisittoreadthissentencewithoutspacestoseparatethewordsfromeachother? :(

None that I've ever found... However, if you think about it a bit, it's really common sense to use spaces to separate words, operators, and numbers in a sentence; which is all XML script is anyway! :( Imeanhowhardisittoreadthissentencewithoutspacestoseparatethewordsfromeachother? :(

And they say reverse polish notation (postfix, or Yoda speak) was a good thing in XML... Not to use blatant sarcasm, I think it would have been so much better if it used octal to aid in the comprehension. This said, there is a tool to convert infix to postfix in the SDK - that seems to avoid this kind of outer space (or was that spaced out?) nonsense :->Etienne

and I thought Fortran was unforgiving! Anyway here is the completed code. Thought I'd throw it in here in case anyone struggled with spaces as long as I did. Fuel Burn and Fuel Range in nm based on number of engines:

			<Element>				<Position X="180" Y="180"/>				<FormattedText X="150" Y="16" Bright="Yes" Length="150" Font="Arial" FontSize="14" LineSpacing="16" Color="#CD8DC5">				<String>Fuel Burn: %((A:NUMBER OF ENGINES, NUMBER))%{case}				%{:4}%((A:Eng1 fuel flow GPH,gallons per hour) (A:Eng2 fuel flow GPH,gallons per hour) (A:Eng3 fuel flow GPH,gallons per hour) (A:Eng4 fuel flow GPH,gallons per hour) + + +)				%{:3}%((A:Eng1 fuel flow GPH,gallons per hour) (A:Eng2 fuel flow GPH,gallons per hour) (A:Eng3 fuel flow GPH,gallons per hour) + +)				%{:2}%((A:Eng1 fuel flow GPH,gallons per hour) (A:Eng2 fuel flow GPH,gallons per hour) +)				%{:1}%((A:Eng1 fuel flow GPH,gallons per hour))%{end}%!4.0d gph</String>				</FormattedText>			</Element>			<Element>				<Position X="180" Y="195"/>				<FormattedText X="150" Y="16" Bright="Yes" Length="150" Font="Arial" FontSize="14" LineSpacing="16" Color="#CD8DC5">				<String>Fuel Range: %((A:NUMBER OF ENGINES, NUMBER))%{case}				%{:4}%((A:Eng1 fuel flow GPH,gallons per hour) (A:Eng2 fuel flow GPH,gallons per hour) (A:Eng3 fuel flow GPH,gallons per hour) (A:Eng4 fuel flow GPH,gallons per hour) + + + 60 / (A:FUEL TOTAL QUANTITY, gallon) r / 60 / (A:GPS Ground Speed, knot) *)				%{:3}%((A:Eng1 fuel flow GPH,gallons per hour) (A:Eng2 fuel flow GPH,gallons per hour) (A:Eng3 fuel flow GPH,gallons per hour) + + 60 / (A:FUEL TOTAL QUANTITY, gallon) r / 60 / (A:GPS Ground Speed, knot) *)				%{:2}%((A:Eng1 fuel flow GPH,gallons per hour) (A:Eng2 fuel flow GPH,gallons per hour) + 60 / (A:FUEL TOTAL QUANTITY, gallon) r / 60 / (A:GPS Ground Speed, knot) *)					%{:1}%((A:Eng1 fuel flow GPH,gallons per hour) 60 / (A:FUEL TOTAL QUANTITY, gallon) r / 60 / (A:GPS Ground Speed, knot) *)%{end}%!03d! nm</String>				</FormattedText>			</Element>

No doubt there is a more elegant way to do this, nevertheless, it works. Thanks for the help, guys.

And they say reverse polish notation (postfix, or Yoda speak) was a good thing in XML... Not to use blatant sarcasm, I think it would have been so much better if it used octal to aid in the comprehension. This said, there is a tool to convert infix to postfix in the SDK - that seems to avoid this kind of outer space (or was that spaced out?) nonsense :->Etienne

Actually FS XML team didn't make the choice for rpn just to complicate gauge programmers, but because it's a very efficient way to handle a scriptying system like the one used in XML code. Most of complex arithmetic and logical operations can be managed with a bunch of very simple low level functions that use rpn method, something that wouldn't be possible with the standard infix notation.Tom