1 REM *** Written by Mark Ray, please read welcome.msg first ***
2 ON ERROR IF ERR=27 THEN CH."AUTO" ELSE REPORT:PRINT " at ";ERL
10 CLS:PRINT 'TAB(20);"Newton Raphson Curve Root Finder"'
20 INPUT LINE "Function Y="F$:INPUT "First Approximation :"U
30 N=0:REPEAT:PRINT "Approximation ";N;" = ";U:X=U
40 U=U-(EVAL(F$)/FNdiff(F$,X)):N=N+1:UNTIL U=X:A=GET:CHAIN"BAG"
60 DEF FNdiff(F$,VX):LOCAL Y1,Y2,X
70 X=VX:Y1=EVAL(F$):X=X*1.000001:Y2=EVAL(F$)
80 =(Y2-Y1)/(X-VX)