Make on value decrease as other increases, with python

Hello, i have run into some sort of a problem, i have to make one value decrease, as other value increases. like so:

Property a is a Float set at 25.000
Property b is a Float set at 0.000

As property b increases way up to 60.000, Property a will decrease to a minimum of 4.000, even though Property b still increases.

Can someone halp me with that?

Many thanks in advance.

if B > 60.0 :
     A -= something
    if A < 4.0 : 
         A = 4.0

can be?

or :

if B > 60.0 :
    dif = B - 60.0
    B = 60.0
    A -= dif
    if A < 4.0 : 
         A = 4.0

I guess that would make B decrease constantly, even though A is not increasing.
It has to be proportional, like if A is 30, B should be 10.5

Or, B will decrease exactly by 1, as A increases exactly by 2.4

There you go:

# bb = b clamped to 0-60.0
bb = max(0.0, min(b, 60.0)) 

a = 25.0 - 21.0 * bb/60.0

Wow, that worked great, i don’t know exactly how it works but, it worked, many thanks!
Could you tell me what exactly this code does?

It does what you described in the first post :slight_smile:
bb is just b, except that it can’t be larger than 60 or smaller than 0

i see, very clever, congratulations!