protocol and data type

[bill516]

Looked at the examples for generic protocol and thought I understood it but now I'm not too sure. How do I tell if the data format is %d or %f, why have some of the formats got a letter= %n.nnf or even %.nf.

<chunk>
<name>heading (rad)</name>
<format>H=%.6f</format>
<type>float</type>
<node>/orientation/heading-deg</node>
<factor>0.0174532925199433</factor> <!-- degrees to radians -->
</chunk>

<chunk>
<name>pitch angle (deg)</name>
<format>P=%03.2f</format>
<node>/orientation/pitch-deg</node>
</chunk>

Another question is why do some of the values in the property tree node have [%d] in them .



Bill

[Hooray]

Hi & welcome,

see: https://en.wikipedia.org/wiki/Printf_format_string

[bill516]

Ok got that thanks.

[%d] is where there are multiple items i.e engines, fuel tanks etc .
X= places a letter before the data item
%n.nnf is a float with a leading zero and two decimal places, etc.

How do I tell if the data is a number or a float?

Bill

[SurferTim]

Look in the internal properties for that property. It will tell you what data type it is.
Be careful. I found that using a float if the data type is a double will cause rounding errors.

[Hooray]

See: http://wiki.flightgear.org/Property_Browser - specifically: "To toggle verbose/developer mode ctrl-click an "." entry."



(admittedly, the wiki could use a corresponding screen shot showing the verbose/developer mode)

[bill516]

Thank s Hooray I think its all sunk in now,

[Hooray]

If you think that this covers grounds that isn't currently covered in the wiki, please do feel invited to add to the wiki accordingly - e.g. by updating the wiki as needed, to add your examples and/or by creating a dedicated little "tutorial" or "howto" - you could also add your example to the newsletter. Again, everything around here is a community-driven effort, so it's your decision to get actively involved in sharing information and contributing your knowledge, so that others can benefit - some of whom may stumble across your postings or articles, even in years to come