Re: problems/risks due to programming language, stories requested

[msb@sq.sq.com (Mark Brader)]

Gerald Baumgartner (gb@cs.purdue.EDU) writes in many groups:
> There is the famous story that a Mariner probe got lost
> because of the Fortran statement `DO 3 I = 1.3' (1.3 instead
> of 1,3) ... It is a nice story but, as far as I know, NASA used
> Jovial at that time and not Fortran.

Just for the record, the above was definitively shown to be fictional
according to authoritative references given in comp.risks (= Risks Digest),
issue 9.75 (I hear), not too many months ago.  There is at least one
textbook that states it as truth; this is wrong.  The actual reason for
the loss of Mariner I was an error in code used in recovering from a
hardware failure; the code had been based on handwritten equations, and
in transcribing one of these, an overbar was deleted from one letter.

A story which may have been the true origin of the "DO statement myth"
was posted fairly recently in alt.folklore.computers; the article
cited a program at NASA that did enter production use with a dot-for-comma
bug in a DO statement, but it wasn't a spacecraft flight control program.
(I didn't save the details and would be happy to see them again.)

Followups directed to alt.folklore.computers.

-- 
Mark Brader			"I'm not going to post a revision: even USENET
utzoo!sq!msb, msb@sq.com	 readers can divide by 100."	-- Brian Reid

This article is in the public domain.