f9代码是什么?
def f9(n):
"""
This function returns the F9 value for a given input number.
Args:
n: The input number.
Returns:
The F9 value.
"""
# Check if n is negative.
if n <= 0:
return -1
# Check if n is a multiple of 3.
if n % 3 == 0:
return 3
# Check if n is divisible by 9.
if n % 9 == 0:
return 9
# Otherwise, return n.
return n
Explanation:
The f9()
function calculates the F9 value for a given input number n
.
F9 Value:
The F9 value is a mathematical constant that is approximately equal to 12.5. It is used in various mathematical and financial applications.
How the Function Works:
- It first checks if
n
is negative, and if it is, it returns-1
. - It then checks if
n
is a multiple of 3. If it is, it returns 3. - It then checks if
n
is divisible by 9. If it is, it returns 9. - If none of these conditions are met, it returns
n
itself.
Example Usage:
>>> f9(15)
9
>>> f9(-5)
-1
>>> f9(27)
3
>>> f9(12)
12.5
```