# tensorplay.testing.assert_close

Source: https://www.tensorplay.cn/docs/generated/tensorplay.testing.assert_close.html

```python
tensorplay.testing.assert_close(actual: Any, expected: Any, *, allow_subclasses: bool = True, rtol: float | None = None, atol: float | None = None, equal_nan: bool = False, check_device: bool = True, check_dtype: bool = True, check_layout: bool = True, check_stride: bool = False, msg: str | Callable[[str], str] | None = None)
```

Asserts that actual and expected are close.

If actual and expected are strided and finite, they are considered
close if

$$\lvert \text{actual} - \text{expected} \rvert \le \texttt{atol} + \texttt{rtol} \cdot \lvert \text{expected} \rvert$$

Non-finite values (-inf and inf) are only considered close if and
only if they are equal. NaN’s are only considered equal to each other
if equal_nan is True.

In addition, they are only considered close if they have the same

- device (if check_device is True),

- dtype (if check_dtype is True),

- layout (if check_layout is True), and

- stride (if check_stride is True).

If either actual or expected is a scalar or a nested python
container, the other side is converted to a tensor-like value before the
comparison.

Parameters:

- actual (Any) – Actual input.

- expected (Any) – Expected input.

- allow_subclasses ([bool](https://docs.python.org/3/builtins/functions.html#bool)) – If True (default) and other than exact type match, inputs that are subclasses of each other are considered close.

- rtol (Optional[[float](https://docs.python.org/3/builtins/functions.html#float)]) – Relative tolerance. If specified atol must also be specified. If omitted, default values based on the dtype are selected. See below for details.

- atol (Optional[[float](https://docs.python.org/3/builtins/functions.html#float)]) – Absolute tolerance. If specified rtol must also be specified. If omitted, default values based on the dtype are selected. See below for details.

- equal_nan ([bool](https://docs.python.org/3/builtins/functions.html#bool)) – If True, two NaN values are considered equal. Defaults to False.

- check_device ([bool](https://docs.python.org/3/builtins/functions.html#bool)) – If True (default), asserts that corresponding tensors are on the same device.

- check_dtype ([bool](https://docs.python.org/3/builtins/functions.html#bool)) – If True (default), asserts that corresponding tensors have the same dtype.

- check_layout ([bool](https://docs.python.org/3/builtins/functions.html#bool)) – If True (default), asserts that corresponding tensors have the same layout.

- check_stride ([bool](https://docs.python.org/3/builtins/functions.html#bool)) – If True, asserts that corresponding strided tensors have the same stride.

- msg (Optional[Union[[str](https://docs.python.org/3/builtins/stdtypes.html#str), Callable[[[str](https://docs.python.org/3/builtins/stdtypes.html#str)], [str](https://docs.python.org/3/builtins/stdtypes.html#str)]]]) – Optional error message to use in case of failure.

Raises:

- [ValueError](https://docs.python.org/3/builtins/exceptions.html#ValueError) – If only rtol or only atol is specified.

- [AssertionError](https://docs.python.org/3/builtins/exceptions.html#AssertionError) – If corresponding values are not close.

Default tolerances by dtype:

| dtype |rtol |atol |
| --- | --- | --- |
| float16 | 1e-3 | 1e-5 |
| bfloat16 | 1.6e-2 | 1e-5 |
| float32 | 1.3e-6 | 1e-5 |
| float64 | 1e-7 | 1e-7 |
| complex64 | 1.3e-6 | 1e-5 |
| complex128 | 1e-7 | 1e-7 |

> **Note**
>
> Tensors are compared elementwise, allowing for a relative and an absolute tolerance per element. If both tolerances are omitted, the loosest tolerance of the involved dtypes is selected.