[R] Data transformation

[jim holtman]

Try this:

> x <- read.table(textConnection("id    code1    code2         p
+  1        4        8           0.1
+  1        5        7           0.9
+  2        1        8           0.4
+  2        6        2           0.2
+  2        4        3           0.6
+  3        5        6           0.7
+  3        7        5           0.9"), header=TRUE)
>  closeAllConnections()
>  # create object like output from 'melt'
>  x.m <- data.frame(id=c(x$id, x$id),
+                    var=paste('var', c(x$code1, x$code2), sep=''),
+                    variable=rep('p', 2*nrow(x)),
+                    value=c(x$p, x$p))
> require(reshape)  # use the reshape package
> (x.n <- cast(x.m, id ~ var, function(.dat){
+     if (length(.dat) == 0) return(0)  # test for no data; return
zero if that is the case
+     mean(.dat)
+ }))
  id var1 var2 var3 var4 var5 var6 var7 var8
1  1  0.0  0.0  0.0  0.1  0.9  0.0  0.9  0.1
2  2  0.4  0.2  0.6  0.6  0.0  0.2  0.0  0.4
3  3  0.0  0.0  0.0  0.0  0.8  0.7  0.9  0.0
>


On Tue, Nov 10, 2009 at 11:10 PM, legen <legendy at gmail.com> wrote:
>
> Thank you for your kind help. Your script works very well. Would you please
> show me how to change NaN to zero and column variables 1, 2, ..., 8 to var1,
> var2, ..., var8? Thanks again.
>
> Legen
>
>
>
> jholtman wrote:
>>
>> Is this what you want:
>>
>>> x <- read.table(textConnection("id    code1    code2         p
>> +  1        4        8           0.1
>> +  1        5        7           0.9
>> +  2        1        8           0.4
>> +  2        6        2           0.2
>> +  2        4        3           0.6
>> +  3        5        6           0.7
>> +  3        7        5           0.9"), header=TRUE)
>>>  closeAllConnections()
>>>  # create object like output from 'melt'
>>>  x.m <- data.frame(id=c(x$id, x$id), var=c(x$code1, x$code2),
>> +     variable=rep('p', 2*nrow(x)), value=c(x$p, x$p))
>>> require(reshape)  # use the reshape package
>>> cast(x.m, id ~ var, mean)
>>   id   1   2   3   4   5   6   7   8
>> 1  1 NaN NaN NaN 0.1 0.9 NaN 0.9 0.1
>> 2  2 0.4 0.2 0.6 0.6 NaN 0.2 NaN 0.4
>> 3  3 NaN NaN NaN NaN 0.8 0.7 0.9 NaN
>>>
>>
>>
>>
>> On Tue, Nov 10, 2009 at 4:30 PM, legen <legendy at gmail.com> wrote:
>>>
>>> Dear all,
>>>
>>> I have a dataset as below:
>>>
>>> id    code1    code2         p
>>>  1        4        8           0.1
>>>  1        5        7           0.9
>>>  2        1        8           0.4
>>>  2        6        2           0.2
>>>  2        4        3           0.6
>>>  3        5        6           0.7
>>>  3        7        5           0.9
>>>
>>> I just want to rewrite it as this (vertical to horizontal):
>>>
>>> id   var1  var2  var3  var4  var5  var6  var7  var8
>>> 1        0      0      0    0.1   0.9       0   0.9    0.1
>>> 2     0.4    0.2   0.6    0.6      0    0.2      0    0.4
>>> 3        0      0      0      0    0.8    0.7    0.9      0
>>>
>>> For the third subject, there are two values being equal to 5 in code1 and
>>> code2, but different values in p:  0.7 and 0.9, so I assigned their
>>> average
>>> 0.8 in var5.
>>>
>>> Does anybody can help me to handle this? Many thanks for your
>>> consideration
>>> and time.
>>>
>>> Legen
>>>
>>> --
>>> View this message in context:
>>> http://old.nabble.com/Data-transformation-tp26291568p26291568.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.
>>>
>>
>>
>>
>> --
>> Jim Holtman
>> Cincinnati, OH
>> +1 513 646 9390
>>
>> What is the problem that you are trying to solve?
>>
>> ______________________________________________
>> 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/Data-transformation-tp26291568p26295766.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.
>



-- 
Jim Holtman
Cincinnati, OH
+1 513 646 9390

What is the problem that you are trying to solve?