Hi ros-users, we went into a strange behaviour of roslaunch, which we don't know, if it is a bug or expected behaviour. Let's consider a config file, which contains a parameter like this: r: rad(0.5 * pi). If I load this file via the rosparam command-line tool r gets correctly converted to "1.5707963267948966". But if I load this file via roslaunch rad and pi will not be converted and the parameter r is 'rad(0.5 * pi)'. The launch file: We tested this under c- and d-turtle. Is this the expected behaviour or a bug? If expected, I will repost my question on answers.ros.org, otherwise I can file a ticket, if desired. :-) Marcus