JZsp98

Program : IMPEULER

Purpose : to plot an approximate solution for the explicit differential equation(DE)
y' = f(x,y) using Heun's method (aka the improved Euler method) -
one of a class of predictor-corrector methods.

Platform: Texas Instruments TI 82/83 graphing calculator

Definition:

Input : The right hand side of the explicit DE , the expression f(x,y) is stored in y₁.
The program prompts for the initial condition (x₀,y₀) and steplength h

Output: A plot of the approximate solution to the initial valie problem y' = f(x,y), y(0)=y₀.

PROGRAM SLOPES Command Locations,

:ClrDraw
:FnOff
:Prompt X
:Prompt Y
:Prompt H
:Lbl P
:X->A
:Y->B
:Y₁->U
:Y+HU->Y
:X+H->X
:B+(HU+Y₁)/2->Y
:Line(A,B,X,Y)
:Goto P
DRAW 1
Yvars On/Off 2
PRGM 2

PRGM Ctl
STO

PRGM CTL 4

Draw 2

PRGM Ctl

Program :	IMPEULER
Purpose :	to plot an approximate solution for the explicit differential equation(DE) y' = f(x,y) using Heun's method (aka the improved Euler method) - one of a class of predictor-corrector methods.
Platform:	Texas Instruments TI 82/83 graphing calculator

Definition:
Input :	The right hand side of the explicit DE , the expression f(x,y) is stored in y₁. The program prompts for the initial condition (x₀,y₀) and steplength h
Output:	A plot of the approximate solution to the initial valie problem y' = f(x,y), y(0)=y₀.