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---
title: MultiStartOptimizer (v0.31)
description: API reference for qiskit.optimization.algorithms.MultiStartOptimizer in qiskit v0.31
in_page_toc_min_heading_level: 1
python_api_type: class
python_api_name: qiskit.optimization.algorithms.MultiStartOptimizer
---
# MultiStartOptimizer
<Class id="qiskit.optimization.algorithms.MultiStartOptimizer" isDedicatedPage={true} github="https://github.com/qiskit-community/qiskit-aqua/tree/stable/0.9/qiskit/optimization/algorithms/multistart_optimizer.py" signature="MultiStartOptimizer(trials=1, clip=100.0)" modifiers="class">
Bases: `qiskit.optimization.algorithms.optimization_algorithm.OptimizationAlgorithm`, `abc.ABC`
An abstract class that implements multi start optimization and should be sub-classed by other optimizers.
Constructs an instance of this optimizer.
**Parameters**
* **trials** (`int`) The number of trials for multi-start method. The first trial is solved with the initial guess of zero. If more than one trial is specified then initial guesses are uniformly drawn from `[lowerbound, upperbound]` with potential clipping.
* **clip** (`float`) Clipping parameter for the initial guesses in the multi-start method. If a variable is unbounded then the lower bound and/or upper bound are replaced with the `-clip` or `clip` values correspondingly for the initial guesses.
## Methods
<span id="qiskit-optimization-algorithms-multistartoptimizer-get-compatibility-msg" />
### get\_compatibility\_msg
<Function id="qiskit.optimization.algorithms.MultiStartOptimizer.get_compatibility_msg" signature="MultiStartOptimizer.get_compatibility_msg(problem)" modifiers="abstract">
Checks whether a given problem can be solved with the optimizer implementing this method.
**Parameters**
**problem** (`QuadraticProgram`) The optimization problem to check compatibility.
**Return type**
`str`
**Returns**
Returns the incompatibility message. If the message is empty no issues were found.
</Function>
<span id="qiskit-optimization-algorithms-multistartoptimizer-is-compatible" />
### is\_compatible
<Function id="qiskit.optimization.algorithms.MultiStartOptimizer.is_compatible" signature="MultiStartOptimizer.is_compatible(problem)">
Checks whether a given problem can be solved with the optimizer implementing this method.
**Parameters**
**problem** (`QuadraticProgram`) The optimization problem to check compatibility.
**Return type**
`bool`
**Returns**
Returns True if the problem is compatible, False otherwise.
</Function>
<span id="qiskit-optimization-algorithms-multistartoptimizer-multi-start-solve" />
### multi\_start\_solve
<Function id="qiskit.optimization.algorithms.MultiStartOptimizer.multi_start_solve" signature="MultiStartOptimizer.multi_start_solve(minimize, problem)">
Applies a multi start method given a local optimizer.
**Parameters**
* **minimize** (`Callable`\[\[`ndarray`], `Tuple`\[`ndarray`, `Any`]]) A callable object that minimizes the problem specified
* **problem** (`QuadraticProgram`) A problem to solve
**Return type**
`OptimizationResult`
**Returns**
The result of the multi start algorithm applied to the problem.
</Function>
<span id="qiskit-optimization-algorithms-multistartoptimizer-solve" />
### solve
<Function id="qiskit.optimization.algorithms.MultiStartOptimizer.solve" signature="MultiStartOptimizer.solve(problem)" modifiers="abstract">
Tries to solves the given problem using the optimizer.
Runs the optimizer to try to solve the optimization problem.
**Parameters**
**problem** (`QuadraticProgram`) The problem to be solved.
**Return type**
`OptimizationResult`
**Returns**
The result of the optimizer applied to the problem.
**Raises**
[**QiskitOptimizationError**](qiskit.optimization.QiskitOptimizationError "qiskit.optimization.QiskitOptimizationError") If the problem is incompatible with the optimizer.
</Function>
## Attributes
### clip
<Attribute id="qiskit.optimization.algorithms.MultiStartOptimizer.clip">
Returns the clip value for this optimizer.
**Return type**
`float`
**Returns**
The clip value.
</Attribute>
### trials
<Attribute id="qiskit.optimization.algorithms.MultiStartOptimizer.trials">
Returns the number of trials for this optimizer.
**Return type**
`int`
**Returns**
The number of trials.
</Attribute>
</Class>