Error while calling julia from python

jl.sind(90) AttributeError: 'Julia' object has no attribute 'sin

[kmsquire]

It seems that defining jl = Julia() inside the function is the source of the problem, although I’m not sure exactly why. If you instead either define jl = Julia() as a global variable, or pass it in as a parameter to the function, everything works fine:

from julia import Julia

jl = Julia()

def harris_jul(frame, lib_func):
    print jl.sind(90)
    return frame

In Julia and most other modern programming languages, globals are discouraged, but in this case, it could be argued that this is a singleton instance that plays a similar role to a module. At any rate, treating it like a singleton, you could do something a little fancier like

from julia import Julia

def julia_singleton():
    if not hasattr(julia_singleton, "__instance"):
        julia_singleton.__instance = Julia()
    return julia_singleton.__instance

def harris_jul(frame, lib_func):
    jl = julia_singleton()
    print jl.sind(90)
    return frame

which seems to work just fine, and is arguably better than a simple global variable.

[karanaggarwal1994]

Is there any check condition that we can put to check if a Julia function with same signature exists then skip it else make it.