CIM4305 Computer Aided Analysis

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CIM4305 - Computer Aided Analysis

• First Order Differential Equations

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Differential Equations

• Use Matlab to get numerical solutions to
  differential equations
• Example

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First Order Differential Equations

• ode45
• Numeric solution to differential equations
• Runge Kutta method

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Using ode45

• NEED TO USE TWO M-FILES!!!!
• Script file to call ode45
• Function file that is called by ode45

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Required Information

• Start time
• Final time
• Initial value of your variable
• Name of your function file

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Example function file

• function dx exampleFunction(x,t)
• dx -x2 t2

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Example script file

• t0 0
• tf 2
• x0 1
• t,x ode45('exampleFunction ,t0 tf,x0)
• plot(t,x)

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This Week

• Read through notes 5
• Complete Exercise 8