TypeError when getting the variable group of a system.

[ElderStack]

When trying to access the variable group of the system, it returns what I think is the memory address of the variables and not a list of the variables.

TypeError: No registered converter was able to produce a C++ rvalue of type std::__1::shared_ptrbertini::node::Variable from this Python object of type VariableGroup

import bertini as b2
from bertini import nag_algorithm
from bertini.nag_algorithm import Slice

x, y, z = b2.Variable('x'), b2.Variable('y'), b2.Variable('z')
f1 = (y - x**2) * (x**2 + y**2 + z**2 - 1) * (x - 2)
f2 = (z - x**3) * (x**2 + y**2 + z**2 - 1) * (y - 2)
f3 = (z - x**3) * (y - x**2) * (x**2 + y**2 + z**2 - 1) * (z - 2)

sys = b2.System()
vars = b2.VariableGroup([x,y,z])
sys.add_variable_group(vars)
sys.add_functions([f1,f2,f3])

slice = Slice.random_complex(sys.variable_groups(), len(sys.degrees()) - 1) #<- Error here

[ofloveandhate]

it's because it wants ONE variable group, not a list of them.

[ElderStack]

gotcha. Totally works now. I thought it was a list of variables, not a list of variable groups.

[ofloveandhate]

re-opening, so i can add a better error message

[ofloveandhate]

Addressed in #305 — variables(['x','y','z']) list form; add_variable_group now accepts loose variables (add_variable_group(x, y, z)), a list, a single Variable, or a VariableGroup; and Slice.random_complex/random_real give a clear message (and unwrap a one-group sequence like sys.variable_groups()) instead of the opaque converter TypeError.