Title Description
Calculate the cube root of a number , Don't use library functions .
Keep one decimal place .
Input description :
Parameters to be solved , by double type （ A real number ）
Output description :
Cube root of input parameter . Keep one decimal place .
Example 1
Input
216
Output
6.0
1、 utilize Scanner Receive typed values .
2、 Newton iterative method is used to solve the cube root , Newton's iterative solution formula (1) Shown , Make the entered value y, Defined function , Then the iterative formula of this problem is as follows (2), Until equation (3) Set up stop iteration .
tips： Rounding reservation 1 Decimal places can be used String Static method of format(“%.1f”, x), among % Represents the number of digits before the decimal point ,1 Means to keep the decimal point 1 position ,f Represents the conversion bit float type （ I looked for it. It seems that there is no one who can convert it to double Of ）
The code implementation is as follows ：
def func():
while True:
try:
a = float(input())
n = 1
while abs(n**3-a) >1e-7:
n = n - (n**3-a)/(3*n**2)
print(round(n,1))
except Exception as e:
#print(e)
break
if __name__ == '__main__':
func()
If using function solutions ：
pow(a,1/3)
