EULERT

TI 85

THIS PROGRAM HAS NOT BEEN TESTED, PLEASE LET US KNOW IF IT WORKS (via "Feedback")

-This program gives values for an approximate solution for the differential equation ${\hbox{dy}\over \hbox{dx}}=\hbox{f(x,y)}$ using Euler's method. The program will ask for initial point, step size, and the number of steps.

Note: Information in {} is not put into the calculator. Information in RED denotes a button on the calculator

Note: Information like BLUE(RED) means to access BLUE hit 2ed then RED

The pause command in the program allow you to see the results of each step. Use ENTER to continue, ON to quit.
An expression for f(x,y) must also be entered in Y1 before running this program. For x use X,T,q,n. For Y use ALPHA then Y.

:0 $\to$ J
:Disp "INITIAL X="	{Disp is found with PRGM in the I/O Menu}
:Input X	{Input is found with PRGM in the I/O Menu, and X should be from the X-VAR key}
:Disp "INITIAL Y="
:Input Y	{Y should be from the variable menu under the graph and draw menu}
:Disp "STEP SIZE="
:Input H
:Disp "NO. OF STEPS="
:Input N
:Lbl P	{Lbl if found with PRGM in the CTL Menu}
:Disp "X,Y:"
:Disp X	{Again, X should be from the X-VAR key}
:Disp Y	{Again, Y should be from the variable menu under the graph and draw menu}
:Pause	{Pause if found with PRGM in the CTL Menu}
:Y+(Y₁*H) $\to$ Y	{As usual, Y should be from the variable menu under the graph and draw menu}
:(X+H) $\to$ X	{As usual, X should be from the X-VAR key}
:IS>(J,N)	{IS> is found with PRGM in the CTL Menu}
:Goto P