Parameters

Some of Classiq's built-in functions can work on parameters (for example, rotation gates).
This guide describes how they can be provided and used.

Using strings

The parameters can be provided to the functions using str.

Example

A single parameter can be provided:

Textual ModelSDK

    {
        "logic_flow": [
            {
                "function": "RZGate",
                "function_params": {
                    "phi": "x"
                }
            }
        ]
    }

from classiq import ModelDesigner
from classiq.builtin_functions.standard_gates import RZGate

model_designer = ModelDesigner()
rz_params = RZGate(phi="x")
model_designer.RZGate(rz_params)
model_designer.synthesize()

Also, parameter expressions can be provided.

Example

Textual ModelSDK

    {
        "logic_flow": [
            {
                "function": "RZGate",
                "function_params": {
                    "phi": "(2 * (x + y)) / 3"
                }
            }
        ]
    }

from classiq import ModelDesigner
from classiq.builtin_functions.standard_gates import RZGate

model_designer = ModelDesigner()
rz_params = RZGate(phi="(2 * (x + y)) / 3")
model_designer.RZGate(rz_params)
model_designer.synthesize()

Using Sympy

Parameters can also be defined by sympy. Note that sympy can be used only in the SDK.

Example

import sympy

from classiq.interface.chemistry.operator import PauliOperator
from classiq.interface.generator.suzuki_trotter import SuzukiParameters, SuzukiTrotter
from classiq import ModelDesigner

model_designer = ModelDesigner()
x = sympy.Symbol("x")
trotter_params = SuzukiTrotter(
    pauli_operator=PauliOperator(pauli_list=[("XXZ", 1), ("YXZ", 0.5)]),
    evolution_coefficient=x,
    suzuki_parameters=SuzukiParameters(order=1, repetitions=1),
)
model_designer.SuzukiTrotter(trotter_params)
model_designer.preferences.draw_at_level = 4
model_designer.synthesize()

When using sympy, mathematical expressions can be used naturally.

Example

```python
import sympy

from classiq.interface.chemistry.operator import PauliOperator
from classiq.interface.generator.suzuki_trotter import SuzukiParameters, SuzukiTrotter
from classiq import ModelDesigner

model_designer = ModelDesigner()
x = sympy.Symbol("x")
y = sympy.Symbol("y")
trotter_params = SuzukiTrotter(
    pauli_operator=PauliOperator(pauli_list=[("XXZ", 1), ("YXZ", 0.5)]),
    evolution_coefficient=(x + y) / 2,
    suzuki_parameters=SuzukiParameters(order=1, repetitions=1),
)
model_designer.SuzukiTrotter(trotter_params)
model_designer.synthesize()
```

Automatically generated parameters

Some functions include many automatically generated parameters. The user may provide the parameter_prefix for the parameter names.

The following functions are: HVA, UCC, and HardwareEfficientAnsatz.

The parameters of two functions with the same parameter_prefix will be regarded as equivalent.