InterpolateBackward {#dev_guide_op_interpolatebackward}
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## General

InterpolateBackward computes the gradients of Interpolate operation.

## Operation attributes

| Attribute Name                                                                               | Description                                                                                              | Value Type |Supported Values                                         | Required or Optional |
|:---------------------------------------------------------------------------------------------|:---------------------------------------------------------------------------------------------------------|:-----------|:--------------------------------------------------------|:----------------------|
| [mode](@ref dnnl::graph::op::attr::mode)                                                     | Specifies type of interpolation                                                                          | string.    | `nearest`, `linear`, `bilinear`, `trilinear`            | Required              |
| [coordinate_transformation_mode](@ref dnnl::graph::op::attr::coordinate_transformation_mode) | Specifies how to transform the coordinate in the resized tensor to the coordinate in the original tensor | string.    | `half_pixel`(default),`align_corners`                   | Optional              |
| [sizes](@ref dnnl::graph::op::attr::sizes)                                                   | Specifies dst shape for spatial axes.                                                                    | s64        | A s64 list containing positive values,`none` is default | Optional              |
| [scales](@ref dnnl::graph::op::attr::scales)                                                 | Specifies `scales` for spatial axes.                                                                     | f32        | A f32 list,`none` is default                            | Optional              |
| [data_format](@ref dnnl::graph::op::attr::data_format)                                       | Controls how to interpret the shape of `src` and `dst`.                                                  | string     | `NCX`, `NXC` (default) -                                | Optional              |

@note Either `sizes` or `scales` should be provided. When `sizes` is
used, `scales` will be ignored.

@note
The attribute `coordinate_transformation_mode` is the name of transformation
mode in string format.\n
Here `scale[x]` is `dst_shape[x]/src_shape[x]` and `x_resized` is a
coordinate in axis `x`,for any axis `x` from the src axis.\n
For `half_pixel`: the coordinate in the original tensor axis `x` is
calculated as `((x_resized + 0.5) / scale[x]) - 0.5`.\n
For `align_corners`: the coordinate in the original tensor axis `x` is
calculated as 0 if `dst_shape[x] == 1` else  `x_resized * (src_shape[x] - 1)
/ (dst_shape[x] - 1)`.

## Execution arguments

The inputs and outputs must be provided according to below index order when
constructing an operation.

### Inputs

| Index | Argument Name | Required or Optional |
|:------|:--------------|:---------------------|
| 0     | `src`         | Required             |
| 1     | `diff_dst`    | Required             |
| 2     | `sizes`       | Optional             |

@note
`src` is original input tensor of Interpolate op.\n
`diff_dst` is the gradient tensor with respect to the dst.\n
`sizes` is a 1D tensor describing output shape for spatial axes.

### Outputs

| Index | Argument Name | Required or Optional |
|:------|:--------------|:---------------------|
| 0     | `diff_src`    | Required             |

@note `diff_src` is the gradient tensor with respect to the src of Interpolate.

## Supported data types

InterpolateBackward operation supports the following data type combinations.

| Src  | Diff_dst | Diff_src | Sizes |
|:-----|:---------|:---------|:------|
| f32  | f32      | f32      | s32   |
| bf16 | bf16     | bf16     | s32   |
| f16  | f16      | f16      | s32   |