Math question about inverting a value

[J Reverb]

vol = reaper.GetMediaTrackInfo_Value( tr, "D_VOL" )
console outputs
3.981071705535
for +12 db
How to get the inverse of this number ?
10^(x/20)
Is their a simple function for this ?
Thanks.
J.

[ErBird]

The answer is in your question. You need to find the inverse function of 10^(x/20).

20*log10(x) or 20*ln(x)/ln(10) depending on what log base you want to use.

[J Reverb]

Ah right I'm still learning this stuff

Will try that out thank you, thank you !

[J Reverb]

Thanks,
So this works to get back to the readable number.

vol = x;
inverted_vol = 20*log10(vol);
newvolume = (ceil(inverted_vol * 10) /10);
Is there a quicker way to do this ?

Ta.