What error code to return for Math.sqrt() overflow condition?

[kraftwerk1611]

Hi,

For Math class in OS there is only one error code related to Math.sqrt()

Sys.error(4) for 'can not compute square root of a negative number'

We are also supposed to check for overflow condition

   [(y+2^j)*(y+2^j)] > 0

What error code should we return if this overflow occurs, the same Sys.error(4) ?

Is there a recommended error code for general/unknown errors?

Thanks.

[cadet1620]

Square root can not overflow.  The square root of 32767, the largest integer, is 181.

In the presented algorithm, (y+2^j)^2 can be greater than 32767, which results in integer overflow. For a safe implementation you do need to check if (y+2^j)^2 overflowed into a negative number. If the overflow occurred, treat it as if it was > x.

t = (y+2^j)^2
if (t <= x and t >= 0)  // t < 0 indicates overflow
    y = y+2^j

--Mark