sofia.field.particle_field¶

class sofia.field.particle_field.ParticleField(name: str, domain: ParticleDomain)¶

Bases: Field

Symbolic field living on a ParticleDomain.

class sofia.field.particle_field.IndexedParticleField(base, *args, **kw_args)¶

Bases: Indexed

A ParticleField indexed by a single particle index, e.g. rho[p_i].

class sofia.field.particle_field.Neighbour(field: Basic)¶

Bases: Function

Value of a particle field at a neighbouring particle.

Only meaningful inside a sum over neighbours.

classmethod eval(field: Basic) → None¶

Returns a canonical form of cls applied to arguments args.

Explanation¶

The eval() method is called when the class cls is about to be instantiated and it should return either some simplified instance (possible of some other class), or if the class cls should be unmodified, return None.

Examples of eval() for the function “sign”

@classmethod
def eval(cls, arg):
    if arg is S.NaN:
        return S.NaN
    if arg.is_zero: return S.Zero
    if arg.is_positive: return S.One
    if arg.is_negative: return S.NegativeOne
    if isinstance(arg, Mul):
        coeff, terms = arg.as_coeff_Mul(rational=True)
        if coeff is not S.One:
            return cls(coeff) * cls(terms)

class sofia.field.particle_field.ParticleLocus(domain: ParticleDomain)¶: Bases: Locus