JZsp98

Program : SLOPES

Purpose : to plot a slopefield for the explicit differential equation
(DE) y' = f(x,y) where the expression f(x,y) is stored in y₁

Platform: Texas Instruments TI 82/83 graphing calculator

Definition: a slopefield for the DE y = f(x,y) is a collection of undirected line segments,
centered at the points {(x_i,y_j)| 1 <=i<= n, 1<= j<= m} with slope f(x_i,y_j).
These segments are tangent to the solution curve y(x) passing through the point (x_i,y_j).

Input : The right hand side of the explicit DE , the expression f(x,y), is stored in y₁.

Output: A plot of the slopefield for the DE y' = f(x,y).

PROGRAM SLOPES Command Locations,

:ClrDraw
:FnOff
:7(Xmax - Xmin)/83->H
:7(Ymax - Ymin)/55->K
:1/(.4*H)²->E
:1/(.4*K)^2->F
:Xmin+H/2->X
:Ymin+K/2->Z
:For(I,1,12,1)
:Z->Y
:For(J,1,8,1)
:Y₁->T
:1/ Ö (E+F*T²)->G
:TG->S
:X->U
:Y->V
:Line(U-G,V-S,U+G,V+S)
:V+K->Y
:End
:U+H->X
:End
Draw 1
Yvars On/Off
Vars Window; STO

PRGM CTL 4

Draw 2

Prgm Ctl

Program :	SLOPES
Purpose :	to plot a slopefield for the explicit differential equation (DE) y' = f(x,y) where the expression f(x,y) is stored in y₁
Platform:	Texas Instruments TI 82/83 graphing calculator

Definition:	a slopefield for the DE y = f(x,y) is a collection of undirected line segments, centered at the points {(x_i,y_j)\| 1 <=i<= n, 1<= j<= m} with slope f(x_i,y_j). These segments are tangent to the solution curve y(x) passing through the point (x_i,y_j).
Input :	The right hand side of the explicit DE , the expression f(x,y), is stored in y₁.
Output:	A plot of the slopefield for the DE y' = f(x,y).