[R] re move row if the column "date_abandoned" has a date in it

[David Winsemius]

On Nov 14, 2009, at 8:43 PM, frenchcr wrote:

>
> sorry David,
>
> im really new to R (my first week) and appreciate your help. Also I  
> dont
> always know what info to give people on the forum (although im  
> starting to
> catch the drift).
>
> heres what i get...
>
> summary(new_data4$date_abandoned)
> Min.        1st Qu.    Median     Mean      3rd Qu.      
> Max.          NA's
> 16010000 19980000 20010000 19930000 20040000  20090000   315732

So new_data4$data_abandoned is not of type "Date" and is instead a  
character vector.

If you are resisting turning it into a date and want to work with  
characters, you can, you just need to deal somehow with the items that  
are not 8 characters wide. What does 315732 represent? How were we  
supposed to interpret the starting "date" you gave of "01010000"?

 > nchar("1010000")
[1] 7

What does table(nchar(new_data4$date_abandoned)) give you?
>
>> ls()
> [1] "data"      "new_data"  "new_data2" "new_data3" "new_data4"
>> small <- head(new_data4, 20)
>> dump("small", 20)
> Error in dump("small", 20) : cannot write to this connection


Well, sorry, I meant to type dump("small", stdout())   ... As per the  
Posting Guide.

-- 
David.
>
> David Winsemius wrote:
>>
>>
>> On Nov 14, 2009, at 5:24 PM, frenchcr wrote:
>>
>>>
>>>
>>> I tried the following but it does the opposite of what i want:
>>>
>>> new_data5 <- subset(new_data4, date_abandoned > "01010000")
>>>
>>> I want to remove the rows with dates and leave just the rows without
>>> a date.
>>>
>>> This removes all the rows that dont have a date in the
>>> date_abandoned column
>>>
>>> ...on a positive note, as i did this next...
>>>
>>> dim(new_data5)
>>> [1] 263  80
>>>
>>> ....i now know that i have 263 dates in that column :)
>>>
>>> I want to remove the 263 rows with dates and leave just the rows
>>> without a
>>> date.
>>
>> Con=me on frenchcr. Stop making us guess. Give us enough information
>> to work with. You asked for something which I construed as saying you
>> wanted dates greater than the the first day of the year 101. You did
>> not address this question.
>>
>> What do you get with str(new_data4) and
>> summary(new_data4$date_abandoned) ? In order to know what sort of
>> comparison to use we need to know what the data looks like.
>>
>> Even better if you offered the output from:
>>
>> small <- head(new_data4, 20)
>> dump("small", 20),
>>
>> -- 
>> David
>>
>>>
>>>
>>>
>>>
>>>
>>>
>>>
>>> David Winsemius wrote:
>>>>
>>>>
>>>> On Nov 14, 2009, at 1:21 PM, frenchcr wrote:
>>>>
>>>>>
>>>>>
>>>>> I want to go through a column in data called
>>>>
>>>> Bad name for a data.frame. Fortunes, "dog" and all that.
>>>>
>>>>> date_abandoned....data["date_abandoned"]....and remove all the  
>>>>> rows
>>>>> that
>>>>> have numbers greater than 1,010,000.
>>>>
>>>> Are you doing archeology? Given what you say next I wondered what
>>>> range you were really asking for.
>>>>
>>>>>
>>>>> The dates are in the format 20091114 so i'm just going to treat  
>>>>> them
>>>>> as
>>>>> numbers for clean up purposes.
>>>>>
>>>>>
>>>>> I know that i use subset but not sure how to proceed from there.
>>>>
>>>> subdata <- subset(data, date_abandoned > "01010000"()
>>>>
>>>>
>>>> The problem with > "1010000" is that your specified minimum point  
>>>> had
>>>> an insufficient number of "places" to be in YYYYMMDD format.
>>>>
>>>> --
>>>>
>>>> David Winsemius, MD
>>>> Heritage Laboratories
>>>> West Hartford, CT
>>>>
>>>> ______________________________________________
>>>> 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.
>>>>
>>>>
>>>
>>> -- 
>>> View this message in context:
>>> http://old.nabble.com/remove-row-if-the-column-%22date_abandoned%22-has-a-date-in-it-tp26352457p26354446.html
>>> Sent from the R help mailing list archive at Nabble.com.
>>>
>>> ______________________________________________
>>> 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.
>>
>> David Winsemius, MD
>> Heritage Laboratories
>> West Hartford, CT
>>
>> ______________________________________________
>> 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.
>>
>>
>
> -- 
> View this message in context: http://old.nabble.com/remove-row-if-the-column-%22date_abandoned%22-has-a-date-in-it-tp26352457p26355689.html
> Sent from the R help mailing list archive at Nabble.com.
>
> ______________________________________________
> 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.

David Winsemius, MD
Heritage Laboratories
West Hartford, CT