[R] Filling in missing values in a column based on previousandfollowingvalues

[Gerrit Eichner]

On Mon, 4 Aug 2014, Florian Denzinger wrote:

> this is great, thanks!
>
> one problem I noticed though is that it fills all NA values in every 
> column, is it possible to specify only one column, e.g. only ID (I have 
> NA values in another column I want to keep)

Yes, of course. Just access only one column, not all: Something like

yourdataframe$ID <- na.locf( yourdataframe$ID)

should replace the ID-column with the modified version you want.

Regards  --  Gerrit


> Kind regards,
> Florian
>
>
>
> Am 04.08.2014 um 11:31 schrieb Gerrit Eichner <Gerrit.Eichner at math.uni-giessen.de>:
>
>> Hello, Florian,
>>
>> function na.locf() from package zoo mightdo what you want.
>>
>> Hth --  Gerrit
>>
>> ---------------------------------------------------------------------
>> Dr. Gerrit Eichner                   Mathematical Institute, Room 212
>> gerrit.eichner at math.uni-giessen.de   Justus-Liebig-University Giessen
>> Tel: +49-(0)641-99-32104          Arndtstr. 2, 35392 Giessen, Germany
>> Fax: +49-(0)641-99-32109        http://www.uni-giessen.de/cms/eichner
>> ---------------------------------------------------------------------
>>
>> On Mon, 4 Aug 2014, fd wrote:
>>
>>> I have the following .csv file containing about 40000 values (here only an
>>> extract and simplified version):
>>>
>>> NAME  ;	YEAR; ID;	VALUE; CUMMB
>>> Sample1;	1998;	 354;	45;	   45
>>> Sample1;	1999;	 354;	23;	   68
>>> Sample1;	2000;	 NA;	66;	   134
>>> Sample1;	2001;	 NA;	98;	   232
>>> Sample1;	2002;	 NA;	36;	   268
>>> Sample1;	2003;	 NA;	59;	   327
>>> Sample1;	2004;	 NA;	64;	   391
>>> Sample1;	2005;	 354;	23;	   414
>>> Sample1;	2006;	 354;	69;	   483
>>> Sample1;	2007;	 354;	94;	   577
>>> Sample1;	2008;	 354;	24;	   601
>>> Sample2;	1964;	1342;	7;	      7
>>> Sample2;	1965;	1342;	24;	     31
>>> Sample3;	2002;	 859;	90;	     90
>>> Sample3;	2003;	  NA;	93;	    183
>>> Sample3;	2004;	  NA;	53;	    236
>>> Sample3;	2005;	 859;	98;	    334
>>>
>>> What I would like to do is to replace the NA values in ID with the values
>>> from the ID. E.g. all values in ID from Sample 1 should have the value 354;
>>> all values in ID from Sample 3 should have the value 859 etc.
>>>
>>> Is there a simple way to do this?
>>>
>>> Thanks for your help.
>>>
>>>
>>>
>>> --
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