Assert runtime invariant: all individuals in `MuPlusLambda::step` need to have a non-None index

[jakobj]

The logic in MuPlusLambda (and likely in other places) assumes that all individuals in a population have been assigned a valid index. We should thus make sure of this in the beginning of this function using an assert.

[xueyongtu]

can't install this package in windows 10, use "python setup.py install" to install hal-cgp-0.3.0.tar.gz, please help me

(base) D:\Download\hal-cgp-0.3.0>python setup.py install
Traceback (most recent call last):
File "setup.py", line 73, in
install_requires=read_requirements(),
File "setup.py", line 25, in read_requirements
with open("./requirements.txt") as f:
FileNotFoundError: [Errno 2] No such file or directory: './requirements.txt'

[xueyongtu]

I also tried other ways to install, all failed

[xueyongtu]

I deal with it by copying the requirements.txt into the file