# Newton–Raphson Method : algorithm for finding roots
# ragulbalaji19

import math

def f(x): return pow(math.e,-x) + x * pow(math.e,-x) - 0.5 # function we want to study
def fprime(x): return -(x * pow(math.e, -x)) # first derivative of said function

starting = [-0.5,0.0,0.5,3.0,3.449,3.5,5.0,6.0,7.0,10.0,40.0] # some starting points to start the process

for pt in starting:
	print("starting @",pt)
	ptn = pt
	for i in range(100): # TIMEOUT ARBITRARILY SET AT 100
		ptnold = ptn
		try:
			ptn = ptn - (f(ptn)/fprime(ptn))
		except Exception as e:
			print("DED", e)
			break;
		print(ptn)
		if abs(ptnold - ptn) < 0.0000001:
			print("CONVERGED.")
			break
	print("---\n")