\START\
\COMMENT=Program file dated 06/28/93, 16:37
\NAME=PARAB
\FILE=parab.85P
Func:FnOff 
Radian
ClLCD
Disp "CHOICE 1"
Disp "Y=A(x-H)\^2\+K"
Disp " "
Disp "CHOICE 2"
Disp "X=A(y-K)\^2\+H"
Disp " "
Input "ENTER 1 OR 2  ",CC
If CC==1
Then
Prompt A
Prompt H
Prompt K
Else
Prompt A
Prompt K
Prompt H
End
10\->\SCALE
abs (1/A)\->\LLR
Lbl AA
\(-)\SCALE\->\xMin
SCALE\->\xMax
\(-)\SCALE\->\yMin
SCALE\->\yMax
If CC==1
Then
"A(x-H)\^2\+K"\->\E1
\St>Eq\(E1,y1)
K+1/(4A)\->\YF
H\->\XF
Else
"K+\sqrt\((1/A)(x-H))"\->\E1
"K-\sqrt\((1/A)(x-H))"\->\E2
\St>Eq\(E1,y1)
\St>Eq\(E2,y2)
H+1/(4A)\->\XF
K\->\YF
End
ZSqr
If CC==1
Then
K-1/(4A)\->\DIR
Line(xMin,DIR,xMax,DIR)
Line(H-LLR/2,YF,H+LLR/2,YF)
Line(XF,yMin,XF,yMax)
Else
H-1/(4A)\->\DIR
Line(DIR,yMin,DIR,yMax)
Line(XF,K+LLR/2,XF,K-LLR/2)
Line(xMin,YF,xMax,YF)
End
Pause 
ClLCD
Disp "(1) ZOOM IN"
Disp "(2) ZOOM OUT"
Disp "(3) NUMERICAL"
Disp "    RESULTS"
Disp ""
Input "ENTER 1,2,3  ",R
If R==3
Goto DD
If R==1
Then
SCALE/2\->\SCALE
Else
SCALE*2\->\SCALE
End
Goto AA

Lbl DD
Disp "VERTEX ="
Disp "X =",H\>Frac\
Disp "Y =",K\>Frac\
Disp " "
Disp "HIT ENTER TO CONTINUE"
Pause 
ClLCD
Disp "FOCUS ="
Disp "X =",XF\>Frac\
Disp "Y =",YF\>Frac\
Disp " "
Disp "HIT ENTER TO CONTINUE"
Pause 
ClLCD
Disp "EQ OF DIRECTRIX IS"
Disp " "
If CC==1
Then
Disp "Y =",DIR\>Frac\
Else
Disp "X =",DIR\>Frac\
End
Disp " "
Disp "HIT ENTER TO CONTINUE"
Pause 
ClLCD
Disp "AXIS OF SYMMETRY IS"
If CC==1
Then
Disp "X =",H\>Frac\
Else
Disp "Y =",K\>Frac\
End

Disp "LENGTH LATUS"
Disp "RECTUM =",LLR\>Frac\
\STOP\