> ## Documentation Index
> Fetch the complete documentation index at: https://tsim.mintlify.site/llms.txt
> Use this file to discover all available pages before exploring further.

# clifford

> Mapping tables for converting parametric rotations with half-pi angles to Clifford gates.

## `expand_clifford_rotations`

```python theme={null}
expand_clifford_rotations(source: stim.Circuit) -> stim.Circuit
```

Return `source` with half-π parametric rotations expanded to Clifford gates.

`REPEAT` blocks are preserved structurally and expanded recursively.

## `is_clifford`

```python theme={null}
is_clifford(source: stim.Circuit) -> bool
```

Return True iff every instruction in `source` is Clifford.

Recurses into `REPEAT` block bodies.

## `parametric_to_clifford_gates`

```python theme={null}
parametric_to_clifford_gates(gate_name: str, params: dict[str, Fraction]) -> list[str] | None
```

Convert a parametric gate with half-π angles to stim Clifford gate names.

**Parameters:**

* `gate_name` (`str`) — One of `"R_X"`, `"R_Y"`, `"R_Z"`, `"U3"`.
* `params` (`dict[str, Fraction]`) — Dict as returned by :func:`~tsim.core.parse.parse_parametric_tag`.

**Returns:**

* `list[str] | None` — Stim gate names in circuit order,
* `list[str] | None` — or `None` when the angles are not half-π multiples.

## `parse_parametric_tag`

```python theme={null}
parse_parametric_tag(instruction: stim.CircuitInstruction) -> tuple[str, dict[str, Fraction]] | None
```

Parse the parametric tag on an instruction (e.g. `I[R_Z(theta=0.3*pi)]`).

Supports gates: R\_Z, R\_X, R\_Y, U3.

**Parameters:**

* `instruction` (`stim.CircuitInstruction`) — The stim instruction whose tag will be parsed.

**Returns:**

* `tuple[str, dict[str, Fraction]] | None` — Tuple of (gate\_name, params\_dict) when the instruction's tag is a
* `tuple[str, dict[str, Fraction]] | None` — well-formed parametric tag, or `None` when the tag is not
* `tuple[str, dict[str, Fraction]] | None` — parametric-looking (no `name(...)` shape, or empty).

**Raises:**

* `ValueError` — When the tag looks parametric (matches `name(...)`) but is malformed: a parameter value does not parse, the gate name is unknown, or the parameter keys do not match the expected set for the gate.