Re: Ada noob here! Is Ada widely used?

[Stephen Leake <stephen_leake@stephe-leake.org>]

"Dmitry A. Kazakov" <mailbox@dmitry-kazakov.de> writes:

> On Fri, 04 Jun 2010 05:08:06 -0400, Stephen Leake wrote:
>
>> "Yannick Duchêne (Hibou57)" <yannick_duchene@yahoo.fr> writes:
>> 
>>> Le Tue, 25 May 2010 04:02:20 +0200, Stephen Leake
>>> <stephen_leake@stephe-leake.org> a écrit:
>> 
>>> What is CMM ?
>> 
>> http://en.wikipedia.org/wiki/Capability_Maturity_Model
>> 
>>>> Commercial airline software is more reliable than the rest of the plane.
>>> I encounter difficulties interpreting this one : do you mean
>>> commercial applications or an airline company are typically more
>>> reliable than the  one its planes ?
>> 
>> I mean the software in embedded computers on an airplane is more
>> reliable than the mechanical components in the airplane.
>
> I wonder how would you (or anyone else) substantiate this claim. 

Just on the basis of news reports of the causes of airplane crashes. To
my memory, none have been due to software. 

> The technical problem is that mechanical components faults have a
> stochastic nature. I.e. you have a certain probability of fault (due
> to physical processes involved in production and function of the given
> component). On the contrary, a software fault is not stochastic,
> neither in its production nor at run-time. A given bug is either here
> or not. 

Whether the bug is encountered is sometimes stochastic. But generally
you are correct.

> There is no probability associated with it. Isn't it comparing apples
> and oranges?

Yes. And they are both fruits, and can be compared to some extent. It's
not like trying to compare science fiction novels and oil wells.

-- 
-- Stephe