R help - Dec 2009 - Problem with date x-axis

Hello,

I have a "friday" problem.
I'm trying to plot the number of measures by day with this command between
the 2008-07-31 and the 2009-11-13 (it works) :
plot(unique(as.Date(strptime(data$date, format="%Y-%m-%d %H:%M:%S))),
measuresbyday)
then I would like to plot vertical lines for each month. 
But it doesn't work because
par()$usr gives
14071.16  14579.84  -7.16  213.16
and
as.numeric(as.POSIXct(unique(as.Date(strptime(data$date, format="%Y-%m-%d
%H:%M:%S)))[1])) corresponding to "2008-08-01" gives
1217376000

I think the last value is ok but I don't understand why the par()$usr values
are so low.

Any idea ?

Thanks in advance and have a nice week-end,
Ptit Bleu.





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PtitBleu wrote:
> Hello,
> 
> I have a "friday" problem.
> I'm trying to plot the number of measures by day with this command
between
> the 2008-07-31 and the 2009-11-13 (it works) :
> plot(unique(as.Date(strptime(data$date, format="%Y-%m-%d %H:%M:%S))),
> measuresbyday)
> then I would like to plot vertical lines for each month. 
> But it doesn't work because
> par()$usr gives
> 14071.16  14579.84  -7.16  213.16
> and
> as.numeric(as.POSIXct(unique(as.Date(strptime(data$date,
format="%Y-%m-%d
> %H:%M:%S)))[1])) corresponding to "2008-08-01" gives
> 1217376000
> 
> I think the last value is ok but I don't understand why the par()$usr
values
> are so low.
> 
> Any idea ?


Seems to be unanswered so far - not a big surprise given we do not see a 
small reproducible example (we do neither have measuresbyday nor data) 
that would be easy and quick to adapt to your needs.

Best wishes,
Uwe Ligges

> Thanks in advance and have a nice week-end,
> Ptit Bleu.
> 
> 
> 
> 
>