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https://issues.apache.org/jira/browse/MATH-195?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=12905077#action_12905077
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Luc Maisonobe commented on MATH-195:
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FunctionEvaluationException is mainly an exception designed for users
functions, its often not an exception commons-math creates by itself.
Numerous example are linked to solving a physical problem (say finding an
energy level in theoretical physics or finding a spacecraft orbit that best
fir a set of observations in a flight dynamics problem). These user functions
may not be computable at some points and the general mathematical algorithm
cannot know it beforehand. So when user code encounters a problem, he must be
able to raise an exception and commons-math must be able to stop in this case.
Although since we currently do not have constrained optimization (except in the
linear case), we cannot prevent the general optimizing algorithm to wander
outside of the user function defining domain and hence violate users function
precondition. So it would be difficult to have a separate policy for
preconditions and for other kinds of errors.
Changing FunctionEvaluatinException to unchecked may be a good move, but our
algorithms should document that these exceptions can arise if user code throws
them.
> Inconsistencies in the Exception hierarchy
> ------------------------------------------
>
> Key: MATH-195
> URL: https://issues.apache.org/jira/browse/MATH-195
> Project: Commons Math
> Issue Type: Improvement
> Affects Versions: 1.1, 1.2, 2.0, Nightly Builds
> Reporter: Thomas Chust
> Assignee: Gilles
> Priority: Minor
> Fix For: 3.0
>
> Original Estimate: 0.17h
> Remaining Estimate: 0.17h
>
> I think there are some inconsistencies in the hierarchy of exceptions used by
> the Commons Math library which could easily be fixed:
> - org.apache.commons.math.linear.MatrixIndexException should really be a
> subclass of
> java.lang.IndexOutOfBoundsException.
> - Either org.apache.commons.math.linear.InvalidMatrixException should be
> checked or
> org.apache.commons.math.random.NotPositiveDefiniteMatrixException and
> org.apache.commons.math.geometry.NotARotationMatrixException should be
> unchecked, but in any case the latter two
> should be subclasses of the former. An unchecked InvalidMatrixException
> should probably be a subclass of
> java.lang.ArithmeticException while a checked InvalidMatrixException
> should be a subclass of
> org.apache.commons.math.MathException.
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