Particles.to_field function to e.g. map Q->Fp/Qp/C.

Author: GDeLaurentis

lips/particle.py

@@ -51,6 +51,12 @@ def __init__(self, kinematics=None, real_momentum=False, field=Field('mpc', 0, 3
         else:
             raise Exception('Bad Particle Constructor')
 
+    def to_field(self, field):
+        self._r_sp_d = numpy.vectorize(field)(self.r_sp_d)
+        self._r_sp_d_to_r_sp_u()
+        self.l_sp_d = numpy.vectorize(field)(self.l_sp_d)
+        self.field = field
+
     def __eq__(self, other):
         """Equality: checks equality of four momenta."""
         if isinstance(other, Particle):

lips/particles.py

@@ -73,6 +73,11 @@ def __init__(self, number_of_particles_or_particles=None, seed=None, real_moment
         else:
             raise Exception(f"Internal masses not understood, received {internal_masses} of type {type(internal_masses)}.")
 
+    def to_field(self, field):
+        for oP in self:
+            oP.to_field(field)
+        self.field = field
+
     def __setattr__(self, name, value):
         if pMVar.match(name):
             self.internal_masses.add(name)

tests/test_particles.py

@@ -151,3 +151,13 @@ def test_hashes_does_not_change_under_identity_mapping():
     # cache_key_hash2 = hashlib.sha256(cache_key_bytes).hexdigest()
     assert hash(oPs) == hash(oPsMapped)
     # assert cache_key_hash1 == cache_key_hash2  # this fails and I'm unsure how to fix it atm
+
+
+def test_field_change():
+    Fp = Field("finite field", 2 ** 31 - 1, 1)
+    oPsFp = Particles(6, field=Field("rational", 0, 0), seed=0)
+    oPsFp.to_field(Fp)
+    Qp = Field("padic", 2 ** 31 - 1, 4)
+    oPsQp = Particles(6, field=Field("rational", 0, 0), seed=0)
+    oPsQp.to_field(Qp)
+    assert oPsFp("⟨1|2⟩") == oPsQp("⟨1|2⟩").as_tuple[0]