[Bug] OneCycleLR object has no attribute 'end',(use before super().__init__())

[whlook]

Prerequisite

• I have searched Issues and Discussions but cannot get the expected help.
• The bug has not been fixed in the latest version(https://github.com/open-mmlab/mmengine).

Environment

obvious code bug
bug code:

mmengine/mmengine/optim/scheduler/param_scheduler.py

Line 987 in c65187c

self.total_steps = self.end - self.begin

Reproduces the problem - code sample

learning policy

param_scheduler = [
dict(
type="OneCycleLR",
eta_max=2e-4,
pct_start=0.3,
div_factor=50,
final_div_factor=1e3,
)
]

Reproduces the problem - command or script

None

Reproduces the problem - error message

AttributeError: 'OneCycleLR' object has no attribute 'end'

Additional information

Param end supports default value, but in OneCycleLR's init, it use self.end before doing super().init() // self.end was defined in Base class.

suggestion:

1. do super.init at the beginning. Or
2. Use end - start but not self.end - self.start

[zhouzaida]

Hi @whlook, thanks for your report and your modification suggestions. I prefer the second suggestion.
Are you interested in making a PR to fix this issue?

[whlook]

Hi @whlook, thanks for your report and your modification suggestions. I prefer the second suggestion. Are you interested in making a PR to fix this issue?

I will make a PR