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Bob J
Bob J

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Newton Method and recursion ?

So I am working on a small python program to run a Newton method recursion!

hers is my code

def newton(a,b):
return newton(a-((a**2 - b )/2*a))

but when I call it

print(newton( 5,27))

I always get this error

"PS C:\Users\Dell\Desktop\pythonstuff\MathPython> python
Traceback (most recent call last):
File "", line 23, in
print(newton( 5,27))
File "", line 11, in newton
return newton(a-((a**2 - b )/2*a))
TypeError: newton() missing 1 required positional argument: 'b'"

Top comments (2)

tobiassn profile image
Tobias SN

When calling newton from inside itself, you’re only passing one parameter to it, which is a. So b doesn’t have any value.

rbjassoc66 profile image
Bob J

thx :-)

current_number = 0 # number of iterations
seed = 5.5 #starting guess
numbertoFindSquareRoot = 37

def newtonMethod():
global current_number
global seed
global numbertoFindSquareRoot
# Base case
if current_number == (6): # max number of iterations
return f'{seed:0.4f}'
# Recursive case
seed = seed - (seed**2 - numbertoFindSquareRoot)/(2*seed)
current_number = current_number + 1
return newtonMethod()