.. _method-nl2sol-initial_trust_radius:

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initial_trust_radius
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Initial trust region radius


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   :maxdepth: 1



**Specification**

- *Alias:* None

- *Arguments:* REAL

- *Default:* -1. (use NL2SOL internal default of 1)


**Description**


``initial_trust_radius`` specification (NL2SOL's ``lmax0``)
specifies the initial trust region radius for the algorithm.

The internal default results in the internal use of steps of length 1.
The default is selected with a value of -1.