Re: union

Vladimir S. Oka wrote: 
Michael Mair wrote:

ramu wrote:

Vladimir S. Oka wrote:


<snip>

PS
Don't get into habit of using floats. Use double instead.

Will you please tell that why we have to use double instead of floats? 

float has fewer significant digits and you get inexact results
_much_ earlier. Usually, you cannot even store all long values
exactly in a float variable.
double has only slightly better guarantees with respect to
the number of digits but in practice has many more.
Using double thus means that you most of the time can forget
about precision (numerics and excessive financial calculation
excluded).
<OT> Apart from that, double is definitely not slower on modern
host PCs </OT>



Also, in many context in a C program, floats will be promoted/converted
to doubles anyway (and maybe then back to float again, if you assign
expression result to a float variable), thus negating any performance
gains you may think you got.


Thanks -- I forgot to mention this; was in my head but did
not run through the fingers... :-)

Cheers
 Michael
--
E-Mail: Mine is an   /at/ gmx /dot/ de   address.
.

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