Hi All,
I am currently implementing a little python script that takes parameters for actions from a string and automatically populates an action goal to send it to the action server. The goal obviously defines all the correct message types like string
, float64
, etc. The problem is, that I read these params from a string that does not necessarily tell me the type, e.g. "30" could be 30, 30.0, or '30', that would depend on the type specified in the goal. I know that for ROS message types like std_msgs/Float64
one can use roslib.message.get_message_class("std_msgs/Float64")
to get the correct python class. But for entries like float64
this becomes more complicated. Even using std_msgs/Float64
does not help because that also contains a float64
in the data
field. My question is, is there a function to get the python type numpy.float64
from 'float64'
in the message definition?
I know there is check_type but that only checks the type to raise an exception but does not return it.
I am on Indigo btw. Here a very small example
def create_goal(str_array):
g = myactionGoal()
for s, slot, t in zip(str_array, g.__slots__, g._slot_types):
t = magic_function_to_get_type_from_string(t)
setattr(g, slot, t(s))
return g
EDIT:
One way of achieving this for simple datatypes would be:
def create_goal(str_array):
g = myactionGoal()
for s, slot, t in zip(str_array, g.__slots__, g._slot_types):
t = type(getattr(g, slot)) # Get type of default value
setattr(g, slot, t(s))
return g
Because after the creation of the goal message, all the slots are intialised with the correct data type. This however does not work for things like float64[]
because that would only tell me that it is supposed to be a list but not the expected type of the elements.
Thanks for your help!
Originally posted by Chrissi on ROS Answers with karma: 1642 on 2016-07-21
Post score: 2