Hello, I have just spent better part of the day trying to work this out. It looks like a bug, but that would be quite interesting in itself. Try this: 
perl -e '$a = "-4.84900000E+001"; $a += 0; $b = -48.49; print "EQ\n" i
+f ($a == $b); print "$a\n$b\n";'

[download]
it gives: 
EQ
-48.49
-48.49

[download]
All good. Now, try this: 
perl -e '$a = "-4.84800000E+001"; $a += 0; $b = -48.48; print "EQ\n" i
+f ($a == $b); print "$a\n$b\n";'

[download]
gives: 
-48.48
-48.48

[download]
? In my main code I am getting scientific notation values as strings, I add 0 and compare them as numbers. It all works, but not for -4.84800000E+001 (and 4.84800000E+001 too). Why? I tried some combinations like 37.37 and so on. 
perl -v
This is perl 5, version 22, subversion 2 (v5.22.2) built for x86_64-li
+nux-thread-multi
(with 33 registered patches, see perl -V for more detail)

[download]
I really do hope this is something silly on my part.

In reply to Converting -4.84800000E+001 to -48.48 doesn't work... but 48.49 does by notameadow

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