Casing in property maps
Formely known as Different outputs for equivalent setups issue
Hallo,
I realised that two setups that should be totally equivalent give different outcomes using different builds.
On the one hand I have config_779ebd6a.info that I run from commit 779ebd6a (22 March), and then I have config_3d3b0d2c.info that I run using commit 3d3b0d2c (20 June).
The two setups are equivalent:
$diff config_779ebd6a.info config_3d3b0d2c.info
25a26
> Artificial true
27c28,30
< Value 1.e-3
---
> Alpha constant {
> Value 1.e-3
> }
82c85
< NbStep 20000
---
> NbStep 10000
namely: \Sigma(r) = \Sigma_0 r^{-\alpha_\Sigma}, \Sigma_0=0.000801137, \alpha_\Sigma=0.5
, h(r) = 0.05
(constant), \alpha(r) = 1.e-3
(constant), a_{pl} = 1, e_{pl} = 0, m_{pl} = 1.e-5
, which is a very normal setup (the NbSteps
are different but this has no effect).
Despite the two setups being the same, I am getting very different evolutions: In particular the final torques (normalised by the planet's mass) are different:
Note that the expected predicted torque value more closely matches the outcome of the 779ebd6a run.
The discs are initialised at exactly the same initial surface density (as it should be since the setup is exactly the same) but end up evolving differently, meaning that the issue is not in the torque output. For example at t=3141.5926536 (500 orbits):
I should note that one difference between the 779ebd6a and the d3b0d2c versions is how the viscosity is implemented, but this should not play a role for such a small planet and relatively high viscosity?
Cheers,
Gabriele