Re: Marina 1 / FORTRAN bug

[robin.vowels@gmail.com]

On Saturday, December 5, 1992 at 7:18:16 AM UTC+11, srhe...@happy.colorado.edu wrote:

> I heard a rumer about a multi-million (or multi-billion) dollar satellite going
> astray because some one left a comma out of a FORTRAN DO loop and it was still
> syntactically legal.  Can anybody give me a reference on this?  

A google search produced this first try:


This has come up in a couple of threads in the last month or two, so I finally got around to looking it up. The famous FORTRAN punctuation error occured on Mariner 1 in 1962. Here is a description of the error:

"There is a useful lesson to be learned from the failure of one of the earliest planetary probes launched by NASA. The cause of the failure was eventually traced to a statement in its control software similar to this:

DO 15 I = 1.100

when what should have been written was:

DO 15 I = 1,100

but somehow a dot had replaced the comma. Because Fortran ignores spaces, this was seen by the compiler as:

DO15I = 1.100
which is a perfectly valid assignment to a variable called DO15I and not at all what was intended."

Information found here:

http://www.star.le.ac.uk/~cgp/prof77.html#tth_sEc1.3