[R] Creating binary variable depending on strings of two dataframes
David Winsemius
dwinsemius at comcast.net
Tue May 10 16:05:27 CEST 2011
On May 10, 2011, at 9:49 AM, noxyport at gmail.com wrote:
> On Tue, May 10, 2011 at 3:09 PM, David Winsemius <dwinsemius at comcast.net
> >
> wrote:
>>
>> On May 10, 2011, at 3:18 AM, noxyport at gmail.com wrote:
>>
>>> On Fri, May 6, 2011 at 7:41 PM, David Winsemius <dwinsemius at comcast.net
>>> >
>>> wrote:
>>>>
>>>> On May 6, 2011, at 11:35 AM, Pete Pete wrote:
>>>>
>>>>>
>>>>> Gabor Grothendieck wrote:
>>>>>>
>>>>>> On Tue, Dec 7, 2010 at 11:30 AM, Pete Pete
>>>>>> <noxyport at gmail.com>
>>>>>> wrote:
>>>>>>>
>>>>>>> Hi,
>>>>>>> consider the following two dataframes:
>>>>>>> x1=c("232","3454","3455","342","13")
>>>>>>> x2=c("1","1","1","0","0")
>>>>>>> data1=data.frame(x1,x2)
>>>>>>>
>>>>>>> y1=c("232","232","3454","3454","3455","342","13","13","13","13")
>>>>>>> y2=c("E1","F3","F5","E1","E2","H4","F8","G3","E1","H2")
>>>>>>> data2=data.frame(y1,y2)
>>>>>>>
>>>>>>> I need a new column in dataframe data1 (x3), which is either 0
>>>>>>> or 1
>>>>>>> depending if the value "E1" in y2 of data2 is true while
>>>>>>> x1=y1. The
>>>>>>> result
>>>>>>> of data1 should look like this:
>>>>>>> x1 x2 x3
>>>>>>> 1 232 1 1
>>>>>>> 2 3454 1 1
>>>>>>> 3 3455 1 0
>>>>>>> 4 342 0 0
>>>>>>> 5 13 0 1
>>>>>>>
>>>>>>> I think a SQL command could help me but I am too inexperienced
>>>>>>> with
> it
>>>>>>> to
>>>>>>> get there.
>>>>>>>
>>>>>>
>>>>>> Try this:
>>>>>>
>>>>>>> library(sqldf)
>>>>>>> sqldf("select x1, x2, max(y2 = 'E1') x3 from data1 d1 left
>>>>>>> join data2
>>>>>>> d2
>>>>>>> on (x1 = y1) group by x1, x2 order by d1.rowid")
>>>>>>
>>>>>> x1 x2 x3
>>>>>> 1 232 1 1
>>>>>> 2 3454 1 1
>>>>>> 3 3455 1 0
>>>>>> 4 342 0 0
>>>>>> 5 13 0 1
>>>>>>
>>>>>>
>>>> snipped Gabor's sig
>>>>>
>>>>> That works pretty cool but I need to automate this a bit more.
>>>>> Consider
>>>>> the
>>>>> following example:
>>>>>
>>>>> list1=c("A01","B04","A64","G84","F19")
>>>>>
>>>>> x1=c("232","3454","3455","342","13")
>>>>> x2=c("1","1","1","0","0")
>>>>> data1=data.frame(x1,x2)
>>>>>
>>>>> y1=c("232","232","3454","3454","3455","342","13","13","13","13")
>>>>> y2=c("E13","B04","F19","A64","E22","H44","F68","G84","F19","A01")
>>>>> data2=data.frame(y1,y2)
>>>>>
>>>>> I want now to creat a loop, which creates for every value in
>>>>> list1 a
> new
>>>>> binary variable in data1. Result should look like:
>>>>> x1 x2 A01 B04 A64 G84 F19
>>>>> 232 1 0 1 0 0 0
>>>>> 3454 1 0 0 1 0 1
>>>>> 3455 1 0 0 0 0 0
>>>>> 342 0 0 0 0 0 0
>>>>> 13 0 1 0 0 1 1
>>>>
>>>> Loops!?! We don't nee no steenking loops!
>>>>
>>>>> xtb <- with(data2, table(y1,y2))
>>>>> cbind(data1, xtb[match(data1$x1, rownames(xtb)), ] )
>>>>
>>>> x1 x2 A01 A64 B04 E13 E22 F19 F68 G84 H44
>>>> 232 232 1 0 0 1 1 0 0 0 0 0
>>>> 3454 3454 1 0 1 0 0 0 1 0 0 0
>>>> 3455 3455 1 0 0 0 0 1 0 0 0 0
>>>> 342 342 0 0 0 0 0 0 0 0 0 1
>>>> 13 13 0 1 0 0 0 0 1 1 1 0
>>>>
>>>> I am guessing that you were to ... er, busy? ... to complete the
>>>> table?
>>>>
>>>> --
>>>>
>>>> David Winsemius, MD
>>>> West Hartford, CT
>>>>
>>>>
>>>
>>> Thanks a lot! Pretty simple. I am so much used to SQLDF right now.
>>>
>>> So how would you handle more complicated strings like that:
>>> y1=c("232","232", "232",
>>> "3454","3454","3455","342","13","13","13","13")
>>> y2=c("E13","B04 A01 F19","B04","F19","A64 G84 A05","E22","H44
>>> C35","F68","G84","F19","A01")
>>> data2=data.frame(y1,y2)
>>>
>>> Where you want to extract for instance all "A01" from the strings?
>>
>> I think you need either to explain what you want in more words of the
>> English language or to offer an example of the desired output. I
>> suspect
> you
>> did not want something as simple as this:
>>
>>> A01.instances <- grep("A01" , data2$y2)
>>> A01.instances
>> [1] 2 11
>>> data2[A01.instances, ]
>> y1 y2
>> 2 232 B04 A01 F19
>> 11 13 A01
>>
>> Or maybe you did?
>>
>> --
>> David Winsemius, MD
>> West Hartford, CT
>>
>>
>
> No, that was not my intention. Consider the following example:
>
> list1=c("A01","B04","A64","G84","F19") # My "substrings" to screen
> for in
>> data2
>>
>>
>> x1=c("232","3454","3455","342","13")
>> x2=c("1","1","1","0","0")
>> data1=data.frame(x1,x2) # Target dataframe where the 5 new binary
>> variables
>> (namely from list1) are added
>>
>>
>> y1=c("232","232", "232",
>> "3454","3454","3455","342","13","13","13","13")
>> y2=c("E133","B04 A01A F194","B04","F19","A642 G84 A05","E223","H44
>> C35","F68","G84","F19","A01")
>> data2=data.frame(y1,y2) # Dataframe to be screen by list1
>>
>
> Result should look like this:
>
> x1 x2 A01 B04 A64 G84 F19
>> 232 1 1 1 0 0 0
>> 3454 1 0 0 1 0 1
>> 3455 1 0 0 0 0 0
>> 342 0 0 0 0 0 0
>> 13 0 1 0 0 1 1
And how were we supposed to figure out that 3454/G84 was not supposed
to be counted?
OK. let's assume you were just sloppy ... then build a new data.frame:
> data4 <- data.frame(y1=rep(data3[,1],
sapply (strsplit(gsub("\\\n"," ",data3$y2), " "),
length) ),
y2 = unlist (strsplit(gsub("\\\n"," ",data3$y2),
" ") ) + )
> data4
y1 y2
1 232 E13
2 232 B04
3 232 A01
4 232 F19
5 232 B04
6 3454 F19
7 3454 A64
8 3454 G84
9 3454 A05
10 3455 E22
11 342 H44
12 342 C35
13 13 F68
14 13 G84
15 13 F19
16 13 A01
--
David Winsemius, MD
West Hartford, CT
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