loop with dates

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Try iterating over the index rather than the value of
each component:

s <- seq(fini,to = ffin, by='days')
for (i in seq_along(s)) print(s[[i]])
Hello,

I am trying to do a loop with dates, but when I try to use the index is not
a date.

  Fcorte <-  as.Date('2008/11/30',format = "%Y/%m/%d")
  fini <- Fcorte + 1
  ffin <- seq(fini,by='months',length=2)[2] - 1

  for (i in seq(fini,to = ffin, by='days'))
   print (weekdays(i))  # i doesn't a date

How can I do a loop with dates and get the index of each date? are there a
method to convert the index i to date?

Thanks in advance.

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-----Original Message-----
From: r-help-bounces at r-project.org 
[mailto:r-help-bounces at r-project.org] On Behalf Of Fernando Bizuet
Sent: Friday, December 12, 2008 12:55 PM
To: r-help at r-project.org
Subject: [R] loop with dates

Hello,

I am trying to do a loop with dates, but when I try to use 
the index is not
a date.
See ?"for". That help page mentions the following which can clarify what
to expect 

"... The variable 'var' has the same type as 'seq' ..."

Small illustration,

fac  <- gl(5,1,labels=letters[1:5])
fac
[1] a b c d e
Levels: a b c d e

typeof(fac)
[1] "integer"

for(i in fac) print(i)
[1] 1
[1] 2
[1] 3
[1] 4
[1] 5
   Fcorte <-  as.Date('2008/11/30',format = "%Y/%m/%d")
   fini <- Fcorte + 1
   ffin <- seq(fini,by='months',length=2)[2] - 1

   for (i in seq(fini,to = ffin, by='days'))
    print (weekdays(i))  # i doesn't a date
typeof(ffin)
[1] "double"

As your index is no longer of class 'Date', you will get
Error in UseMethod("weekdays") : no applicable method for "weekdays
How can I do a loop with dates and get the index of each 
date? are there a
method to convert the index i to date?
Here's one way 
dd <- seq(fini,to = ffin, by='days')
for (i in seq_along(dd)) print(dd[i])

Thanks in advance.

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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.