[ITK-users] (R wrapping/SimpleITK) AddCommand to ImageRegistrationMethod bug

[Mathew Guilfoyle]

Richard

Thanks for the reply.  I hadn't appreciated that function being passed in the registration example was a closure.  However, in the FiterProgressReporting example it is not a closure.  

I have modified my code to be a closure but still get a crash/abort; I have also run the code in the examples themselves verbatim and get the same problem.

Any further ideas on how to get this working?

Cheers 


> On 10 Apr 2016, at 02:10, Mathew Guilfoyle <mrguilfoyle at gmail.com> wrote:
> 
> There seems to be a problem with using the $AddCommand function to ImageRegistrationMethod objects in the R wrapping to SimpleITK.
> 
> Using R 3.2.4 on OS X 10.11
> 
> Example:
> 
> f <- function(x){print(x$GetMetricValue())}
> 
> registration = ImageRegistrationMethod()
> 
> registration$AddCommand(‘sitkIterationEvent’, f(registration))
> 
> This last line causes R to abort/hard crash (no error message).  This behaviour is irrespective of which event type I use or the function passed as the second argument (e.g. even something simple like print(‘Hello’))
> 
> The AddCommand method is inherited from the SimpleITK ProcessObject type.  Digging around in the SimpleITK.R file I can see that the ProcessObject$AddCommand method expects a second argument of type ‘_p_itk__simple__Command’.
> 
> There is a ‘Command’ method that generates a new object of type ‘_p_itk__simple__Command’.  If I pass this resulting object as the second argument to registration$AddCommand then I do not get an error.  However, there doesn’t seem to be any way to point the ‘_p_itk__simple__Command’ object to my function or otherwise convert my function to a ‘_p_itk__simple__Command’ type.
> 
> The $AddCommand method is used in a couple of example scripts on the SimpleITK site (using it for monitoring a registration and a filter e.g. https://github.com/SimpleITK/SimpleITK/blob/master/Examples/FilterProgressReporting.R) so I don’t know if it was working previously and a bug has been introduced more recently? (the example scripts cause the same error when I run them now)
> 
> 
>