Implement PICMI flag to set `compute_max_step_from_btd` (#3740)

* Implement PICMI flag for setting max_step from btd

* Update Python/pywarpx/picmi.py

Co-authored-by: Edoardo Zoni <59625522+EZoni@users.noreply.github.com>

---------

Co-authored-by: Edoardo Zoni <59625522+EZoni@users.noreply.github.com>

1 files changed, 7 insertions, 0 deletions

diff --git a/Python/pywarpx/picmi.py b/Python/pywarpx/picmi.py
index ce82ea5c9..9a2f7f7f2 100644
--- a/Python/pywarpx/picmi.py
+++ b/Python/pywarpx/picmi.py
@@ -1489,6 +1489,11 @@ class Simulation(picmistandard.PICMI_Simulation):
     warpx_zmax_plasma_to_compute_max_step: float, optional
         Sets the simulation run time based on the maximum z value
 
+    warpx_compute_max_step_from_btd: bool, default=0
+        If specified, automatically calculates the number of iterations
+        required in the boosted frame for all back-transformed diagnostics
+        to be completed.
+
     warpx_collisions: collision instance, optional
         The collision instance specifying the particle collisions
 
@@ -1526,6 +1531,7 @@ class Simulation(picmistandard.PICMI_Simulation):
         self.amr_check_input = kw.pop('warpx_amr_check_input', None)
         self.amr_restart = kw.pop('warpx_amr_restart', None)
         self.zmax_plasma_to_compute_max_step = kw.pop('warpx_zmax_plasma_to_compute_max_step', None)
+        self.compute_max_step_from_btd = kw.pop('warpx_compute_max_step_from_btd', None)
 
         self.collisions = kw.pop('warpx_collisions', None)
         self.embedded_boundary = kw.pop('warpx_embedded_boundary', None)
@@ -1551,6 +1557,7 @@ class Simulation(picmistandard.PICMI_Simulation):
             pywarpx.warpx.boost_direction = 'z'
 
         pywarpx.warpx.zmax_plasma_to_compute_max_step = self.zmax_plasma_to_compute_max_step
+        pywarpx.warpx.compute_max_step_from_btd = self.compute_max_step_from_btd
 
         pywarpx.algo.current_deposition = self.current_deposition_algo
         pywarpx.algo.charge_deposition = self.charge_deposition_algo