[Rcpp-devel] Datetime substraction bug ?

[Robin Girard]

Thanks you're right  I already wrote it myself with getFractional...
and indeed that's not really what we should call a "bug" but it took me a while to understand that 

if date1-date2>0  then date1<date2 ;)

R.


----- Mail original -----
De: "Dirk Eddelbuettel" <edd at debian.org>
À: "Robin Girard" <robin.girard at mines-paristech.fr>
Cc: rcpp-devel at lists.r-forge.r-project.org
Envoyé: Samedi 30 Mars 2013 00:44:08
Objet: Re: [Rcpp-devel] Datetime substraction bug ?


On 29 March 2013 at 23:37, Robin Girard wrote:
| Hi List
| 
| why is it that we have in the Datetime definition
| (here http://dirk.eddelbuettel.com/code/rcpp/html/Date_8cpp_source.html#l00271 )
| 
| double operator-(const Datetime& d1, const Datetime& d2) { return d2.m_dt - d1.m_dt; }
| bool operator<(const Datetime &d1, const Datetime& d2) { return d1.m_dt < d2.m_dt; }
| 
| I feel there is a contradiction 
| substraction shoulb be d1.m_dt - d2.m_dt;  no ? 

It's been a while since I wrote that and I think I followed the difftime()
convention in R. Or maybe not.  To me d1 comes before d2 in the way the
arguments are given, so d2 is larger and I want to subtract d1 from d2.

In any event, if it bugs you greatly you are always free to write your own
function. ;-)

Dirk

| 
| Robin
| 
| Dr. Girard Robin
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