ESA's Schiaparelli Mars probe crashed because of integer overflow

Walter Bright via Digitalmars-d digitalmars-d at puremagic.com
Sat Nov 26 15:13:27 PST 2016


On 11/26/2016 3:16 AM, deadalnix wrote:
> On Saturday, 26 November 2016 at 05:50:19 UTC, Walter Bright wrote:
>> It reminds me of college, where we were told that if we worked a problem and
>> came up with unreasonable answers, such as negative energy, we were expected
>> to note:
>>
>>    "I know this answer is unreasonable, but I cannot find the mistake."
>>
>> and the worst you'd get is a 0. Unreasonable answers, and no note, meant you'd
>> get a negative score!
>
> You got a great teacher right there !
>

It was actually institute policy, not an individual teacher's. Another policy is 
no grades can be based on attendance (unless it was P.E.). A third is that if 
you can pass the finals, you can opt out of any class and yet receive full 
credit for it. A fourth was grades will not be on a curve - you either met the 
standard or you didn't.

There's more.

Oh, one more you'll recognize. You'd get a 0 on any computation where you 
prematurely rounded the results :-) The algebra had to be worked out to its 
final form before plugging in numbers. (Lots of times intermediate terms would 
algebraically cancel out, so calculating intermediate values would result in 
spurious rounding errors.)

I thought it was a fairly enlightened system of grading, quite a step up from 
what I was used to.




More information about the Digitalmars-d mailing list