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

# E0010 — InputDimensionMismatch

> The input spike raster has a different feature count than the model's first layer.

<Warning>E0010: input dimension mismatch</Warning>

## What happened

You passed a spike raster with `got` input features to a model that expects `expected` input features. The dimensions do not match and the model cannot run.

## Why

The model was compiled for a specific input size (e.g. 700 for SHD). The input you provided has a different number of features.

## How to fix

1. **Check your encoder output shape.** The raster shape should be `[T, n_features]` where `n_features` matches the first layer's `in_features`.
2. If you are using `thrindex.encoders`, verify the `n_channels` parameter matches the model architecture.
3. If you are building input manually, check that you are not transposing T and N dimensions.

## Example

```
E0010: input dimension mismatch: model expects 700 input neurons, got 784.
Why: the input spike train does not match the model's first layer.
Fix: verify your encoder output shape matches the model architecture.
Docs: https://docs.thrindex.com/errors/E0010
```

## Common mistake

MNIST has 784 pixels. SHD has 700 cochlear channels. If you accidentally pass an MNIST-encoded input to an SHD model, you get this error.