Thank you David for the clarification. You are absolutely right.

Best,
Jorge


On Fri, Nov 13, 2009 at 9:30 PM, David Winsemius <> wrote:

>
> On Nov 13, 2009, at 7:46 PM, Jorge Ivan Velez wrote:
>
>  Hi Rachel,
>>
>> Here is a suggestion:
>>
>> index <- sample(100)
>> mysample <- gly[index, ]
>> mysample
>>
>>
> I doubt that was what he was hoping to get (which would be a permutation of
> 1:100 rather than a subsample).
>
> try:
> samp <- gly[ sample(nrow(gly), 100), ]
>
> --
> David
>
>
>  See ?sample for more information.
>>
>> HTH,
>> Jorge
>>
>>
>> On Fri, Nov 13, 2009 at 5:20 PM, Hayes, Rachel M <> wrote:
>>
>>  Hi All,
>>>
>>>
>>>
>>> I want to take a simple random sample from a large dataset, gly, but I'm
>>> getting an error message.  Any help?
>>>
>>>
>>>
>>> dim(gly)
>>>
>>> [1] 112371     37
>>>
>>>  s1 <- sample(gly,100)
>>>>
>>>
>>> Error in `[.data.frame`(x, .Internal(sample(length(x), size, replace,  :
>>>
>>>
>>> cannot take a sample larger than the population when 'replace = FALSE'
>>>
>>
> It is not a misleading error once you consider that the length of a
> data.frame, which is what you handed to sample(), is the number of columns
> rather than the number of rows. Data.frames are lists.
>
> --
>
> David Winsemius, MD
> Heritage Laboratories
> West Hartford, CT
>
>

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