I should have said, those date vairable are indeed date variables, but I'll
try some of these techniques as soon as I get in this morning.

Thanks so much for your input.

- Eric

On Tue, Dec 27, 2011 at 6:54 AM, Jorge I Velez <jorgeivanvelez@gmail.com>wrote:

> Try also
>
> subset(x, as.Date(Inspected, "%m/%d/%y") > as.Date(Sold, "%m/%d/%y") )
>
> HTH,
> Jorge.-
>
>
>
> On Mon, Dec 26, 2011 at 9:32 PM, Jorge I Velez <> wrote:
>
>> Hi Eric,
>>
>> Try
>>
>> # data
>> x <- structure(list(House_number = 1:4, Inspected = structure(c(3L,
>> 4L, 1L, 2L), .Label = c("10/31/2011", "8/3/2011", "9/2/2011",
>> "9/4/2011"), class = "factor"), Sold = structure(c(1L, 2L, 4L,
>> 3L), .Label = c("10/10/2011", "10/20/2011", "11/1/2011", "8/28/2011"
>> ), class = "factor")), .Names = c("House_number", "Inspected",
>> "Sold"), class = "data.frame", row.names = c(NA, -4L))
>>
>> > with(x, as.Date(Inspected, "%m/%d/%y") - as.Date(Sold, "%m/%d/%y") > 0)
>> [1] FALSE FALSE  TRUE FALSE
>>
>> > x[with(x, as.Date(Inspected, "%m/%d/%y") - as.Date(Sold, "%m/%d/%y") >
>> 0), ]
>>   House_number  Inspected      Sold
>> 3            3 10/31/2011 8/28/2011
>>
>> See ?as.Date for more information.
>>
>> HTH,
>> Jorge.-
>>
>>
>>
>> On Mon, Dec 26, 2011 at 7:52 PM, Eric Wolff <> wrote:
>>
>>> Hi,
>>>
>>> I hope this isn't a really simple question, I've been struggling with it
>>> for a while.
>>>
>>> I'm looking for a way to get a function to go through a data frame line
>>> by
>>> line, compare fields, and produce a result, kind of a transform and an if
>>> statement combined (I tried to put them together and it didn't work).
>>>
>>> So, consider data Sales:
>>>
>>> House number     Inspected    Sold
>>> 1                           9/2/2011     10/10/2011
>>> 2                          9/4/2011      10/20/2011
>>> 3                          10/31/2011    8/28/2011
>>> 4                           8/3/2011     11/1/2011
>>>
>>> I want to find all the records which were inspected after they were sold.
>>> Ideally, this code would create a fourth field that would be a logical.
>>>
>>> I tried
>>>
>>> Sales<-transform(Sales, Checked=if(Sales$Inspected <= Sales$Sold) "OK")
>>>
>>> But that busted. I've bent over backward to make these kinds of
>>> comparisons
>>> work, but there has to be a better way. Any help would be most welcome.
>>>
>>> Thanks,
>>>
>>> Eric
>>>
>>>        [[alternative HTML version deleted]]
>>>
>>> ______________________________________________
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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.
>>>
>>
>>
>

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