R help - Nov 2012 - zoo timeseries plot; minor tic mark level control

I cannot figure out how to tune the minor tic marks on the date axis of a
zoo plot.

I read hundreds of CSV files from a zip archive transparently. The
time/date strings I convert to POSIXct format, order them and then make a
zoo object as there may be cases which have unequal time stamping. As
follows:
######################
#Transform timestamps and reorder them
dat <- transform(dat, Timestamp = as.POSIXct(Timestamp, format =
"%m/%d/%Y
%H:%M:%S", tz ="Europe/Paris"))
dat<-dat[order(dat$Timestamp),]

#Make a zoo object
zdt <- zoo(dat[,2:4], dat$Timestamp)

#Plot
plot.zoo(zdt,main=mttl,xlab=NULL,panel=panel.yaxis,
         yaxt='n',type = 'l',cex=0.2)
#####################

The plot is easy. For this data the timestamping is every 5 seconds over
many weeks (2 to 3 months). The standard tic mark labeling I get with the
plot.zoo() is just the abbreviated name of the month (Oct and Nov). How
can I add minor tic marks for the individual days?

All and any help or pointers welcome.
Alex van der Spek

On Mon, Nov 26, 2012 at 6:36 AM, Alex van der Spek <doorz at xs4all.nl>
wrote:
> I cannot figure out how to tune the minor tic marks on the date axis of a
> zoo plot.
>
> I read hundreds of CSV files from a zip archive transparently. The
> time/date strings I convert to POSIXct format, order them and then make a
> zoo object as there may be cases which have unequal time stamping. As
> follows:
> ######################
> #Transform timestamps and reorder them
> dat <- transform(dat, Timestamp = as.POSIXct(Timestamp, format =
"%m/%d/%Y
> %H:%M:%S", tz ="Europe/Paris"))
> dat<-dat[order(dat$Timestamp),]
>
> #Make a zoo object
> zdt <- zoo(dat[,2:4], dat$Timestamp)
>
> #Plot
> plot.zoo(zdt,main=mttl,xlab=NULL,panel=panel.yaxis,
>          yaxt='n',type = 'l',cex=0.2)
> #####################
>
> The plot is easy. For this data the timestamping is every 5 seconds over
> many weeks (2 to 3 months). The standard tic mark labeling I get with the
> plot.zoo() is just the abbreviated name of the month (Oct and Nov). How
> can I add minor tic marks for the individual days?
>
> All and any help or pointers welcome.
> Alex van der Spek
>
> ______________________________________________
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> PLEASE do read the posting guide
http://www.R-project.org/posting-guide.html
> and provide commented, minimal, self-contained, reproducible code.
See the examples in ?plot.zoo . Several of  those have major and minor
tick marks.

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