[CHANGESET] reallog, realpow and realsqrt functions

[John W. Eaton]

On 21-Mar-2008, David Bateman wrote:

| Here is a patch that adds these three rather trivial functions that
| return an error if the return value is complex.

I applied it.

| Funnily to be matlab
| compatible "realpow(1i,2)" is allowed. These are matlab core functions,
| though I wonder how much they are really used..

I guess these are useful if you are doing something iterative and you
expect the results to be real, but it is possible that an iteration
may stray into a region that generates complex values?  If so, then
why not also "real" versions of acos, acosh, asin, atanh, and log10
(and maybe others)?  But seriously, I don't see a need to add them.

Thanks,

jwe