From murdoch at stats.uwo.ca  Sun Jan 29 19:08:57 2006
From: murdoch at stats.uwo.ca (Duncan Murdoch)
Date: Sun, 29 Jan 2006 13:08:57 -0500
Subject: [Rd] [R] help with read.table() function
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On 1/29/2006 12:55 PM, Marc Schwartz wrote:
> I would argue against this.
> 
> If this were the default, that is requiring user interaction, it would
> break a fair amount of code that I (and I am sure a lot of others have)
> where automation is critical.

I don't see how this change could affect any code that currently works 
-- maybe you misunderstood the proposal?  I'm just suggesting that the 
args to functions that take input from files use file.choose() as a 
default.  For example, read.table's arg list would change from

function (file, header = FALSE, ...

to

function (file = file.choose(), header = FALSE, ...

Currently a call like read.table() dies with an error message:

 > read.table()
Error in read.table() : argument "file" is missing, with no default

With this change we wouldn't get an error here.

> 
> A lot of the issues seem to be user errors, file permission errors,
> hidden extensions as is pointed out below and related issues. If there
> is a legitimate bug in R resulting in these issues, then let's patch
> that. However, I don't think that I can recall reproducible situations
> where a bug in R is the root cause of these problems.

This isn't about fixing a bug, it's about making the user interface a 
bit less error-prone.

Duncan Murdoch

> 
> Best regards,
> 
> Marc Schwartz
> 
> On Sun, 2006-01-29 at 12:18 -0500, Duncan Murdoch wrote:
>> (Moved from R-help).
>>
>> This comes up often enough that I'm starting to think most functions 
>> that take filename arguments should have file.choose() as the default 
>> value.  Then one could do
>>
>> read.table()
>>
>> and have a dialog box pop up in Windows, or some other prompt for a 
>> filename in other platforms.  Are there any obviously bad side effects 
>> from a change like this?
>>
>> Duncan Murdoch
>>
>> On 1/29/2006 11:51 AM, Peter Dalgaard wrote:
>>> Romain Francois <francoisromain at free.fr> writes:
>>>
>>>> Le 29.01.2006 16:26, oliver wee a ?crit :
>>>>
>>>>> hello, I have just started using R for doing a project
>>>>> in time series...
>>>>>
>>>>> unfortunately, I am having trouble using the
>>>>> read.table function for use in reading my data set.
>>>>>
>>>>> This is what I'm getting:
>>>>> I inputted:
>>>>> data <-
>>>>> read.table("D:/Oliver/Professional/Studies/Time Series
>>>>> Analysis/spdc2693.data", header = TRUE)
>>>>>
>>>>> I got:
>>>>> Error in file(file, "r") : unable to open connection
>>>>> In addition: Warning message:
>>>>> cannot open file 'D:/Oliver/Professional/Studies/Time
>>>>> Series Analysis/spdc2693.data', reason 'No such file
>>>>> or directory'
>>>>>
>>>>> as I am just a novice programmer, I really would
>>>>> appreciate help from you guys. Is there a need to
>>>>> setpath in R, like in java or something like that...
>>>>>
>>>>> I am using the windows version btw. 
>>>>>
>>>>> I have also tried to put the file in the work
>>>>> directory of R, so that I only typed 
>>>>> data <- read.table("spdc2693.data", header = TRUE)
>>>>> Again, it won't work, with the same error message.
>>>>>
>>>>> I would appreciate any help. thanks again.
>>>>>  
>>>>>
>>>> Hi, try :
>>>>
>>>> read.table(file.choose(), header=TRUE)
>>>>
>>>> and go to your file.
>>>> Also, you can look a ?setwd, ?getwd
>>> Right. Or just file.choose() and see what the OS thinks your file is
>>> really called. The most common causes for symptoms like that are
>>>
>>> (A) The file is "spcd2693.data"
>>> (B) There's an extra extension which ever helpful Windows decided to
>>> hide, as in "spdc2693.data.txt".
>>>
>>>
>> ______________________________________________
>> R-devel at r-project.org mailing list
>> https://stat.ethz.ch/mailman/listinfo/r-devel
> 
> ______________________________________________
> R-devel at r-project.org mailing list
> https://stat.ethz.ch/mailman/listinfo/r-devel



[Rd] [R] help with read.table() function
Duncan Murdoch