ppvm_sym (crate)

ppvm_sym¶

ppvm_sym

Symbolic, parametric Pauli propagation.

`ppvm-sym` provides a Term type that represents a polynomial in sines and cosines of symbolic parameters. It is used by ppvm to propagate Pauli operators through parametric circuits (e.g., variational ansätze) without committing to specific angle values until the very end.

Quick example

Build the symbolic expression `sin(x0) * cos(x1)`, then evaluate it at a concrete `(x0, x1)`:

``` use ppvm_sym::Term;

let expr = Term::var(0).sin() * Term::var(1).cos();

let v = expr.eval(&[0.5, 1.0]).unwrap(); let expected = 0.5_f64.sin() * 1.0_f64.cos(); assert!((v - expected).abs() < 1e-12); ```