[R] Adding two files into one and vlookup

[Raghu]

I was able to achieve the desired output. The issue I had was that
both the files contained the Date column in the data format. So, i
first converted this colum alone into numeric and then did a merge on
the files and it worked. The moral is that in any dataframe all
variable have to be of similar type and then merge works. Correct me
if i am wrong?

On 7/7/10, Raghu <r.raghuraman at gmail.com> wrote:
> Say I have two files file and file2:
>
> file1 contains the following:
> Date	                Price
> 02/07/2010	53.96597903
> 03/07/2010	56.92825807
> 04/07/2010	39.27408645
> 05/07/2010	42.59834151
> 06/07/2010	70.68512383
> 07/07/2010	10.92505265
> 08/07/2010	52.12492249
> 09/07/2010	49.88767957
>
> file2 contains the following:
> Date	                Price
> 03/07/2010	5.312006403
> 04/07/2010	673.0705924
> 05/07/2010	442.4679386
> 06/07/2010	851.9158985
> 07/07/2010	581.8592424
>
> I want to create a new file that should look like:
> Date                  Price1                Price2
> 03/07/2010	5.312006403        56.928
> 04/07/2010	673.0705924        39.274
> 05/07/2010	442.4679386        42.598
> 06/07/2010	851.9158985        70.685
> 07/07/2010	581.8592424        10.925
>
> Thx
>
>
>
> On 7/7/10, Erik Iverson <eriki at ccbr.umn.edu> wrote:
>> raghu wrote:
>>> I have two files with dates and prices in each. The number of rows in
>>> each
>>> of
>>> them will differ. How do I create a new file which contains data from
>>> both
>>> these files? Cbind and merge are not helpful. For cbind because the rows
>>> are
>>> not the same replication occurs. Also if I have similar data how do I
>>> write
>>> a vlookup kind of function? I am giving an example below:
>>> Say Price1 file contains the following:
>>> Date             Price
>>> 2/3/2010       134.00
>>> 3/3/2010       133.90
>>> 4/3/2010       135.55
>>>
>>> And say price2 contains the following:
>>> Date              Price
>>> 2/3/2010        2300
>>> 3/3/2010        3200
>>> 4/3/2010        1800
>>> 5/3/2010        1900
>>>
>>> I want to take both these data together in a single file, and take the
>>> smaller vector (or matrix or dataframe??..i am new to R and still
>>> confused
>>> with the various objects) which is file1 (because it contains fewer rows
>>> )
>>> and vlookup prices in the second file basedon the dates on file1 and
>>> write
>>> three columns (date, price from 1 and price from2) in a new file. How do
>>> i
>>> do this please?
>>
>> I think all this can be accomplished with merge.  Can you give
>> reproducible
>> examples as the posting guide suggests?
>>
>> Use read.table to read in your data into R objects, then use ?dput to
>> give
>> us
>> the exact copies of the objects (probably data.frames by your example),
>> and
>> what
>> output you want to have.  Being precise with the classes of objects
>> you're
>> working with is key, and ?dput is a great way to make sure we have the
>> same
>> objects as you.
>>
>> Another tip is common terminology. For instance, `vlookup` is not a term
>> used in
>> R, and many people will not know what it means.
>>
>> This way, everything is reproducible for us, and we can offer suggestions
>> and
>> show you what the exact output will be.  In short, making sure everyone
>> is
>> on
>> the same page goes a long way when getting help from a mailing list.
>>
>>
>
>
> --
> 'Raghu'
>


-- 
'Raghu'