'ProgramMode:RUN
Menu "Use _GraphY_1 for dy//dx?","Yes",1,"No, let me type it",0
Lbl 0
"Type dy//dx (use X,Y)"?->Str 1
Str 1->GraphY1
Lbl 1
"dx (step size)"?->H
"How many steps"?->N
"X0"?->X
"Y0"?->Y
1+N->N
{N,4}->Dim Mat A
For 1->I To N Step 1
X->Mat A[I,1]
Y->Mat A[I,2]
If I<N
Then 
GraphY1(X)->Mat A[I,3]
H*GraphY1(X)->Mat A[I,4]

IfEnd
Y+GraphY1(X)*H->Y
X+H->X
Next
ClrText
Locate 1,6,"Y _#E6B1_ "
Locate 5,6,Mat A[N,2]
Locate 1,3,"Steps in _Mat _A"
Locate 1,4,"1   2    3     4"
Locate 1,5,"X   Y  dy//dx   _#E543_y"
Do:Getkey
LpWhile  Not Ans
Mat ADispsStop