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LECTURE 10: CONSTRAINED OPTIMIZATION – OPTIMALITY CONDITIONS 1. Basic concepts 2. Necessary conditions – KKT conditions 3. Sufficient conditions

LECTURE 10: CONSTRAINED OPTIMIZATION – OPTIMALITY CONDITIONSocw.nctu.edu.tw/course/np982/Lecture10.pdf · LECTURE 10: CONSTRAINED OPTIMIZATION – OPTIMALITY ... constraint is active

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Page 1: LECTURE 10: CONSTRAINED OPTIMIZATION – OPTIMALITY CONDITIONSocw.nctu.edu.tw/course/np982/Lecture10.pdf · LECTURE 10: CONSTRAINED OPTIMIZATION – OPTIMALITY ... constraint is active

LECTURE 10: CONSTRAINED OPTIMIZATION – OPTIMALITY CONDITIONS

1. Basic concepts2. Necessary conditions – KKT conditions3. Sufficient conditions

Page 2: LECTURE 10: CONSTRAINED OPTIMIZATION – OPTIMALITY CONDITIONSocw.nctu.edu.tw/course/np982/Lecture10.pdf · LECTURE 10: CONSTRAINED OPTIMIZATION – OPTIMALITY ... constraint is active

Constrained optimization• General form: Short form:

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Basic concepts• Definition:

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Basic concepts• Definition

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Basic concepts• Definition

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Basic concepts• Theorem:

• Proof:Luenberger P. 298.

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First order necessary conditions• NLP with equality constraints• Theorem:

• Proof: Directly from Taylor's Theorem, or Luenberger P. 300.

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First order necessary conditions• Corollary:

• Proof:

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Observations

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First order necessary conditions• NLP with equality and inequality constraints

• Definition

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Main theorem• Theorem (KKT Conditions)

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Proof

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Common terminologies

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Constraint qualifications (CQ)• Slater’s condition (Slater’s CQ) Other CQs

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Second order necessary conditions• Observations:

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Result 1

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Result 2

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Sufficient conditions for optimality• Key idea: Following the 2nd-order sufficient conditionsfor unconstrained optimization problem will lead to ananswer to the constrained case.

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Result 1

Proof:Luenberger P. 307 proved explicitly by contradiction.

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Observations

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Result 2

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Observations

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Interesting questions

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Answer to question 1

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Answer to question 1

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Answer to question 2

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Answer to question 2