A doubt in DIFFUSE example

Hello everyone,

I couldn’t figure this out in in.msd.2d where a line reads :

variable twopoint equal c_msd[4]/4/(step*dt+1.0e-6)

I know Einstein’s equation : msd=2nDdt where n is the number of dimensions. What does this 1.0e-6 represent? Shouldn’t this be simply :
variable twopoint equal c_msd[4]/4/(step
dt)

Thanks,
Sonu Kumar

Probably just a trick to avoid a division by zero.

Kristof

Exactly. So that on step 0, you get a slope = 0.

Steve