nkdsl.Update

class Update(_program=None)

Immutable, chainable site-update program builder.

Every instance method appends one operation and returns a new Update object, the original is never mutated. The canonical entry points are the module-level free functions (shift(), write(), swap(), permute(), affine(), scatter(), identity()) which avoid the Update() boilerplate.

Parameters:

_program (UpdateProgram | None) – Internal update program (do not pass manually).

__init__(_program=None)

Parameters:

_program (UpdateProgram | None)

Return type:

None

Methods

__init__([_program])
affine(site_ref, *, scale[, bias])	Appends x'[i] = scale * x[i] + bias.
cond(predicate, *, if_true[, if_false])	Returns a new Update wrapping a JAX-compatible conditional.
hop(src, dst, *[, amount])	Appends an occupation transfer from src to dst.
invalidate(*[, reason])	Marks this branch as invalid (zero matrix element).
permute(*site_refs)	Appends a cyclic rotation over K sites.
scatter(flat_indices, values)	Appends bulk writes to static flat site indices.
shift(site_ref, delta)	Appends x'[i] = x[i] + delta.
shift_mod(site_ref, delta)	Appends a Hilbert-aware wrapped shift.
swap(site_a, site_b)	Appends x'[a], x'[b] = x[b], x[a].
to_program()	Returns the underlying immutable UpdateProgram.
write(site_ref, value)	Appends x'[i] = value.