# CSE535 Numerical Computation

## Keith on Numerical

[ KeithOnNumerical.pdf ] (PDF)

## Numerical Solution of Ordinary Differential Equations

### Euler

"To every problem there is a simple, obvious solution that just doesn't work." H L Menken's Law.

### Runge Kutta Methods

(RK4 matlab): from web [ ode.m ] or [ ode.cpp ] translated into C++.

(Wikipedia): [ Runge_Kutta ]

(Stack overflow discussion): Better games through Numerical [ runge-kutta-rk4-integration-for-game-physics ]

(deriving simple Runge-Kutta Methods at MIT): Taylor Series any one? [ node5.html ]

(Text video powerpoint pdfs on RK4): Amazing teach-yourself resource [ runge_kutta_4th_method.html ]

#### Exercise -- the 32.2 foot pendulum

Solve
1. y''+sin(x)=0,

First we have to rewrite in the standard form of y'=f(x,y), by adding a new variable,

3. v := dy/dx.
4. (above)|-v'= y''.

5. v' = -sin(x),
6. y'(0)=0,
7. y' = v,

Cockled up solution [ ex.cpp ]

What is wrong with this code? Suggest to ways of improving it.

Conclusion: TBA.

. . . . . . . . . ( end of section Exercise) <<Contents | End>>

### Lab Manual

[ Lab_main.pdf ] (PDF)

### Other stuff on ODEs

(ODEs on Wolfram Alpha): too easy [ ?i=ordinary+differential+equation ]

[ log.txt ]

# Abbreviations

1. TBA::="To Be Announced".
2. TBD::="To Be Done".