[R] Need help on parsing dates

[Ajay Shah]

I know this:

  > library(date)
  > x="1979-04-04"
  > try=as.date(x, "ymd")
  > print(try)
  [1] 4Apr79

and that `x' here has to be a string, e.g.:

  > x=1979-04-04
  > print(x)
  [1] 1971

I'm stuck in reading from a file. I say:  

  > A <- read.table(file="try")
  > print(A)
             V1          V2
  1  1979-04-04 -1.04712042
  2  1979-04-06  0.54538055
  3  1979-04-09  0.09663392
  4  1979-04-11  0.57119871
  5  1979-04-12  0.73594112
  6  1979-04-17 -1.54422087
  7  1979-04-18 -0.20595691
  8  1979-04-19  0.12700429
  9  1979-04-20  0.42016807
  10 1979-04-23 -1.46838241

I am confused - is V1 a number or a string? Looking at it, it must be
a string. But yet:

  > library(date)
  > try=as.date(A$V1, "ymd")
  Error in as.date(A$V1, "ymd") : Cannot coerce to date format

In short, how do I parse in dates of the format yyyy-mm-dd (the ISO
8601 format) or the yyyymmdd format.

And if I may ask the next step: How do I tell R that I have a file
full of data all of which is time-series data, where V1 is the
datetime vector, and all the other columns are time-series, to do
things like ARMA models and ts plots with?

-- 
Ajay Shah                                                   Consultant
ajayshah at mayin.org                      Department of Economic Affairs
http://www.mayin.org/ajayshah           Ministry of Finance, New Delhi