How to modify a parameter?

I’m a new one here. I have started to use Ardupilot since 2 weeks so I don’t know everything yet…
My question is : can I modify a parameter range ? In fact, AVOID_DIST_MAX range is 1-30 but I wanted it to be 0.5-30 for exemple. Is it possible ? Where can I do it in the code and how ?

The 1 - 30 range is just a range that will suit most users and protect against typos. Feel free to set the value to whatever you like.

Disclamer: ranges are more important for some params than others don’t ignore then all

Thank you for your return.

But how do I set the value ? In Mission planner it says that it’s not possible when I set the param at 0.5. Is there a thing in the code that I have to do ?

Are you in the advanced view (config->planner->layout) on the full param list/tree?

Yes I’m in advanced layout

Just tested in SITL,

I just hit Yes and it saves, maybe your seeing something else?

Oh it was with a , and not a . !
Thank you so much it’s working.
Sorry for wasting your time, have a nice day