All issues PTC-W0028

Anti-pattern

Major

Autofix Calculating the length of the hypotenuse using the standard formula `c = sqrt(a**2 + b**2)`

may lead to overflow if the two other sides are both very large.
Even though `c`

will not be much bigger than `max(a, b)`

, either `a**2`

or `b**2`

(or both) could be. Thus, the calculation could overflow, even though the result is well within representable range.
It is recommended to use the built-in function `hypot(a,b)`

from the `math`

library.

Example:

```
from math import sqrt, hypot
a = 3e154 # a^2 > 1e308
b = 4e154 # b^2 > 1e308
# with these, c = a^2 + b^2 = 5e154 which is less than 1e308
def hypotenuseDirect():
return sqrt(a**2 + b**2) # This will give an `OverflowError`
def hypotenuseBuiltin():
return hypot(a, b) # This will give the expected result, without overflowing
```