Category : Recently Uploaded Files
Archive   : PAPCW10.ZIP
Filename : ROOT.PRG

; calculate root of x^3 - (6 * x^2) + (11 * x) - 1 = 0 using Newton's method
; correct answer is 0.0958
LBL findroot
E-10 0 sto ; tolerance
0.9 ; initial guess
100.00001 1 sto ; loop counter for max iterations
LBL loop
DUP DUP XEQ f OVER XEQ fprime / - ; calculate x'
DUP ROT -
ABS
0 RCL <=
GTO OK
DROP
1 DSE
GTO loop
PUTS "No convergence after 100 iterations\n"
RTN
LBL OK
DROP
PUTS "Answer = " 0 WIDTH 4 FIX PUTSTACK PUTS "\n\n"
DROP
RTN

LBL f ; x^3 - (6 * x^2) + (11 * x) - 1
DUP 3^ OVER 2^ 6* - SWAP 11* + 1-
RTN

LBL fprime ; (3*x^2) - (12*x) + 11
DUP 2^ 3* SWAP 12* - 11+
END