[R] Help in running Stata dataset in R

[Prof Brian Ripley]

Your examples work for me via read.dta() and via use(), including the Date 
columns, with the current foreign_0.8-28.  They also work on Windows 2.7.1 
with foreign_0.8-26.

As far as I can see the only relevant part of read.dta is 
as.Date("1960-1-1"): you might want to try that to see if it malfunctions.
If it does, it is possible that the problem is in your timezone setting -- 
the CHANGES file says

     o   An attempt is made (once per session) to identify the current
         timezone from the Windows' Registry.  If this does not work or
         is incorrect, set the 'TZ' environment variable appropriately:
         a list of known timezones is given in
         R_HOME/share/zoneinfo/zones.tab ...

So you could start R with TZ="Africa/Nairobi" at the end of the command 
line (assuming you are physically in Kenya and your machine is set to 
Kenyan time).


On Wed, 6 Aug 2008, Lazarus Mramba wrote:

> Dear Prof Brian,
>
> It is true that i used the epicalc package. The functions use() and
> des() are from epicalc.
> The problem does not occur if i use library(foreign) : tmp <-
> read.dta("maltreat.dta", convert.dates=FALSE)
>
>>  sessionInfo()
> R version 2.7.1 (2008-06-23)
> i386-pc-mingw32
>
> locale:
> LC_COLLATE=English_United States.1252;LC_CTYPE=English_United
> States.1252;LC_MONETARY=English_United
> States.1252;LC_NUMERIC=C;LC_TIME=English_United States.1252
>
> attached base packages:
> [1] splines   stats     graphics  grDevices utils     datasets  methods
>
> [8] base
>
> other attached packages:
> [1] epicalc_2.7.1.2 survival_2.34-1 foreign_0.8-26
>
>
> library(foreign)
>> tmp <- read.dta("maltreat.dta", convert.dates=FALSE)
>> str(tmp)
> 'data.frame':   670 obs. of  43 variables:
>
> ## thanks. able to read the dataset.
> However, epicalc function use() cannot call the data.
>
> library(epicalc)
>> use("maltreat.dta")
> Error in fromchar(x) :
>  character string is not in a standard unambiguous format
>
>
> use("malvac.dta")
> Error in fromchar(x) :
>  character string is not in a standard unambiguous format
>
>
> ## I have attached the two datasets herein
>
>
>
>
>
> Kind regards,
> Lazarus Mramba
> Junior Statistician
> P.O Box 986, 80108,
> Kilifi, Kenya
> Mobile No. +254721292370
> Tel: +254 41 522063
> Tel: +254 41 522390
> (office extension : 419)
>
>>>> Prof Brian Ripley <ripley at stats.ox.ac.uk> 08/06 12:38 PM >>>
> What are use() and des()?  Please note the footer of this message.
> (Are you using package epicalc without telling us?)
>
> I suspect that foreign::read.dta is being used.  That has argument
> 'convert.dates', and you could try setting it to FALSE, as the message
> is
> from as.Date.character() complaining about the date format.
>
> It is likely that the difference is in the version of 'foreign' and not
> in
> the version of R: the posting guide asked for the output of
> sessionInfo()
> which would have told us which versions these were.
>
> In short, try
>
> library(foreign)
> tmp <- read.dta("maltreat.dta", convert.dates=FALSE)
> str(tmp)
> tmp$dob
> tmp$todaydate
>
> and if the latter two are numbers, try converting them by e.g.
>
> as.Date(tmp$dob, origin="1960-01-01")
>
> It would help to make the dataset available for the developers to
> investigate.
>
> On Wed, 6 Aug 2008, Lazarus Mramba wrote:
>
>> Dear All,
>>
>> I installed R 2.7.0 and tried to call a dataset i had ealier own
> called
>> on R2.6.2 but i keep on getting an error:
>> use("maltreat.dta")
>>
>> Error in fromchar(x) :
>>  character string is not in a standard unambiguous format
>>
>> Tried doing the same with R2.7.1 but i get the same error.
>>
>> However if i call the same on R 2.6.2, there is no error:
>>
>> use("maltreat.dta")
>>> des()
>>
>> No. of observations =  670
>>   Variable          Class           Description
>> 1  scrno             integer
>> 2  todaydate         Date
>> 3  ethnic            character
>> 4  othtribe          character
>> 5  dob               Date
>> 6  ageyrs            integer
>> 7  agemths           integer
>> 8  sex               character
>>
>> I cannot figure out what the problem is.
>>
>> Please help me.
>>
>>
>>
>> Kind regards,
>> Lazarus Mramba
>> Junior Statistician
>> P.O Box 986, 80108,
>> Kilifi, Kenya
>> Mobile No. +254721292370
>> Tel: +254 41 522063
>> Tel: +254 41 522390
>> (office extension : 419)
>>
>> ______________________________________________
>> 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.
>>
>
> -- 
> Brian D. Ripley,                  ripley at stats.ox.ac.uk
> Professor of Applied Statistics,  http://www.stats.ox.ac.uk/~ripley/
> University of Oxford,             Tel:  +44 1865 272861 (self)
> 1 South Parks Road,                     +44 1865 272866 (PA)
> Oxford OX1 3TG, UK                Fax:  +44 1865 272595
>

-- 
Brian D. Ripley,                  ripley at stats.ox.ac.uk
Professor of Applied Statistics,  http://www.stats.ox.ac.uk/~ripley/
University of Oxford,             Tel:  +44 1865 272861 (self)
1 South Parks Road,                     +44 1865 272866 (PA)
Oxford OX1 3TG, UK                Fax:  +44 1865 272595