+0 and -0 and SQRT in Fortran77

[G.W.Bultman]

Hi,

A small Fortran problem of moderately general interest. 

On our HP9000, a single precision real can represent +0 and -0
( 00 00 00 00  and  80 00 00 00 ).

For all purposes, such as adding etc. this does not create any problems,
but when the SQRT is taken, -0 generates a NaN.

This, of course, is rather unfortunate, as we have a program which 
does several divisions of the type x/y, where x can be 0.0 and y can be
-1.0, thus generating a -0. 

Can anyone offer a solution or other helpful comments?

Thanks,
Gert.

Please reply to me directly: bultmanadgw.rws.nl
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