Download - Introduction to Numerical Analysis I

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Page 1: Introduction  to  Numerical Analysis  I

Introduction to Numerical Analysis I

MATH/CMPSC 455

Ordinary Differential Equations

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MODEL PROBLEM

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EULER’S METHOD

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Example

Example

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TAYLOR SERIES METHOD

Idea: keep more terms in the Taylor expansion

A Example (keep second order term)

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Example

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RUNGE-KUTTA METHODS

A drawback of Taylor Series Method is that it involves derivatives of

Idea: use to express derivatives

2nd order Runge-Kutta Methods:

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4th order Runge-Kutta Methods:

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BACKWARD EULER METHOD

Backward Euler Method:

Differences:• Implicit• Need to solve an equation (maybe

expensive)

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COMPARISON (FROM FPI POINT OF VIEW)

Example:

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COMPARISON (FROM STABILITY POINT OF VIEW)

Example:

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HOW TO SOLVE THE EXTRA EQUATION

Example: