PROGRAM TRAPINT (solving integrals using the trapaziod method)

Lbl 0
ClrHome
Disp "CURRENT FUNCTION"
Disp "IS STORED IN Y1"
Disp "ENTER N"
Prompt N
If N<=0
Goto 0
Disp "ENTER TOP"
Prompt B
Disp "ENTER BOTTOM"
Prompt A
ClrHome
Disp "TOP CANT BE <="
Disp "BOTTOM"
Disp "1,RETRY"
Disp "2,QUIT"
Disp "3,CONTINUE"
Input Q
If Q=1
Then
ClrHome
Goto R
End
If Q=2
Stop
ClrHome
End
((B-A)/N)-->C
0-->E
C-->F
0-->G
0-->L
0-->X
2-->V
Menu("DISPLAY OUTPUT?","YES",Y,"NO,N)
Lbl Y
1-->K
Goto 1
Lbl N
0-->K
Lbl 1
If G=0
Then
A-->X
((0.5)(Y1))-->I
If K=1
Then
Output(1,1,"(1/2)*")
Output(1,7,Y1)
Output(1,16,"+")
End
End
(C+A)-->X
If K=1
Then
Output(V,1,Y1)
Output(V,16,"+")
(1+L)-->L
If L>=4
Then
(V+1)-->V
If (G+1)=N
Then
(V-1)-->V
Output(V,1,"                ")
End
Output(V,1,"PRESS ENTER")
Pause
ClrHome
0-->L
1-->V
End
End
(Y1+E)-->E
(C+F)-->C
(1+G)-->G
(V+1)-->V
If G>=N
Then
Goto 2
End
Goto 1
Lbl 2
(V-1)-->V
(E-Y1)-->E
If K=0
Then
1-->V
End
If K=1
Then
Output(V,1,"                ")
Output(V,1,"(1/2)*")
Output(V,1,Y1)
(V+1)-->V
Output(V,1,"ALL *")
Output(V,6,F)
End
((0.5)(Y1))-->H
((F)(I+H+E))-->J
If K=1
Then
(V+1)-->V
Output(V,1,"PRESS ENTER")
Pause
End
ClrHome
Output(1,1,"AREA =")
Output(2,1,J)
Stop



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Notes
  --to get Y1 use (2nd, VARS, Enter, Enter)
  -- >=, and <= can be accessed through (2nd, MATH)
  --Requires that a valid function be entered into Y1 under the "Y=" key.