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# atol

The absolute convergence tolerance.

```
var atol: Double
```

## Discussion

*‖ b-Ax ‖₂ < ``doc://com.apple.accelerate/documentation/Accelerate/SparseGMRESOptions/rtol`` * ‖ b-Ax₀ ‖₂ + ``doc://com.apple.accelerate/documentation/Accelerate/SparseGMRESOptions/atol``* indicates convergence.

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