Thank you very much for implementing compute heat/flux.
Just bringing to your notice a few typos in “compute heat/flux” documentation page.
In the example at the end of the page:
1> As mentioned in the documentation, a compute pe/atom needs to be added
compute PE all pe/atom pair
2> The line:
compute flux all heat_flux
compute flux all heat/flux PE
3> The line:
variable J equal c_flux1/vol
variable J equal c_flux/vol