[R] time plotting problem

[John Kane]

I clearly spoke too soon.  

With the actual data I am not getting sensible x-axis
units.  The program with the actual data below.  Graph
output is here:
http://ca.geocities.com/jrkrideau/R/hd.png .  

I seem to be getting only a single entry for the
x-axis of "2007". However dates range from
 First Date    Last Date 
"2006-09-26" "2007-11-10" 

I must be missing something blindingly obvious but I
don't see it. 

Thanks for any suggestions.


Actual data and test program
================================================
mydata <-
read.table("http://ca.geocities.com/jrkrideau/R/heartdata.txt",
sep="\t",
             header=FALSE)
mydata[,1] <- as.Date(mydata[,1],"%m/%d/%y")
names(mydata) <- Cs(dates, sy,dys,pulse, weight)
minmax  <-  c(max(mydata[,2]),min(mydata[,2]),
max(mydata[,3]),min(mydata[,3]))
names(minmax) <- c("maxsys", "minsys", "maxdsy",
"mindys") ; minmax 

min.max.dates <- c(min(mydata[,1]), max(mydata[,1]))
names(min.max.dates) <- c("First Date", "Last Date");
min.max.dates

ss <- lm(mydata[,2]~mydata[,1])
plot(mydata[,1],mydata[,2], xlab="Dates", ylab="Blood
pressure",  
       ylim=c(minmax[4], minmax[1]), col= "red",
type="l")
abline (ss, col ="yellow")
dd <- lm(mydata[,3]~mydata[,1])
points(mydata[,1], mydata[,3], type="l", col="blue" )
abline(dd, col= "yellow", lwd=2)






> Thanks to Gabor and Jim. I am not sure if the first
> entry year = 2009 is all the problem I'm getting but
> it is certainly seems like the worst of it.  
> 
> My stupidity:  Someone sent me the data set in Excel
> 
> and I didn't do the basic data checks on. I _KNEW_
> the
> data went from 2006 to 2007. 
> 
> --- Gabor Grothendieck <ggrothendieck at gmail.com>
> wrote:
> 
> > In your examples the first line of your data
> refers
> > to the
> > year 2009 and Oct 1st is repeated.  Is that really
> > what
> > you meant?
> > 
> > I can't tell what your problem is from your
> > description
> > other than the data problems cited but there are
> > lots of
> > examples of plotting with zoo in the following
> which
> > may
> > help you:
> > vignette("zoo")
> > vignette("zoo-quickref")
> > ?plot.zoo
> > ?xyplot.zoo
> > 
> > Note that zoo series must be time series, i.e.
> they
> > must
> > have unique times.
> > 
> > On Nov 12, 2007 1:47 PM, John Kane

> > > I am completely misunderstanding how to handle
> > dates.
> > > I want to plot a couple of data series against
> > some
> > > dates.  Simple example 1 below works fine.
> > > Unfortunately I have multiple observations per
> day
> > (no
> > > time breakdowns) and observations across years.
> > > (example 2 very simplistic version )
> > >
> > > Can anyone suggest a quick fix or point me to
> > > something to read?  I thought that zoo might do
> it
> > but
> > > I seem to be missing something there too.
> > >
> > > Any suggestions gratefully recieved.
> > >
> > >
> > > Example 1 consecutive dates same year.
> > >
> =================================================
> > > x <- "days
> > > 9/26/09
> > > 9/27/06
> > > 9/28/06
> > > 9/29/06
> > > 9/29/06
> > > 9/29/06
> > > 10/1/06
> > > 10/1/06
> > > 10/2/06
> > > 10/3/06"
> > >
> > > mydata <- read.table(textConnection(x),
> > header=TRUE,
> > > as.is=TRUE); mydata
> > >
> > > mydates <- as.Date(mydata[,1], "%m/%d/%y");
> > mydates
> > > mynums <- rnorm(10)
> > > plot(mydates, mynums)
> > > ================================================
> > > Example 2 (things go blooy!)
> > > non-consecutive dates different years.
> > >
> > >
> =================================================
> > > x <- "days
> > > 9/26/09
> > > 9/27/06
> > > 9/28/06
> > > 9/29/06
> > > 9/29/06
> > > 9/29/06
> > > 10/1/07  # <- year changes
> > > 10/1/07
> > > 10/2/07
> > > 10/3/07"
> > >
> > > mydata <- read.table(textConnection(x),
> > header=TRUE,
> > > as.is=TRUE); mydata
> > >
> > > mydates <- as.Date(mydata[,1], "%m/%d/%y");
> > mydates
> > > mynums <- rnorm(10)
> > > plot(mydates, mynums)
> > >
> > > ______________________________________________
> > > R-help at r-project.org mailing list
> > > https://stat.ethz.ch/mailman/listinfo/r-help
> > > PLEASE do read the posting guide
> > http://www.R-project.org/posting-guide.html
> > > and provide commented, minimal, self-contained,
> > reproducible code.
> > >
> >
> 
> ______________________________________________
> R-help at r-project.org mailing list
> https://stat.ethz.ch/mailman/listinfo/r-help
> PLEASE do read the posting guide
> http://www.R-project.org/posting-guide.html
> and provide commented, minimal, self-contained,
> reproducible code.
>