[R] Alternative to loops

Ek Esawi e@@w|ek @end|ng |rom gm@||@com
Mon Apr 8 02:02:57 CEST 2019


Thank you Bert. It did indeed work and i put it in one line as well.
The match(TRUE..) through me off a little on the beginning, but i
realized why it's there.
Thanks for your continuous comments on mine and many other posts.

EK

On Sat, Apr 6, 2019 at 5:07 PM Bert Gunter <bgunter.4567 using gmail.com> wrote:
>
> I skipped pre-populating MyDF$C as unnecessary:
>
> > MyDF <- data.frame(A=c(1,2,3,4,5),B=c("aa ab ac","bb bc bd","cc cf","dd","ee"),
> + stringsAsFactors = FALSE)
>
> ## I think this does what you want:
>
> > choices<- sapply(MyDF$B, strsplit, split = " +")
> > nm <- names(MyList)
> > MyDF$C <- nm[sapply(choices, function(x)match(TRUE, sapply(MyList,function(tbl)any(x %in% tbl))))]
> > MyDF$C
> [1] "Y" "z" "X" NA  NA
>
> You could of course make this even more opaque by making it a one-liner. ;-)
>
> Cheers,
> Bert
>
>
>
> On Sat, Apr 6, 2019 at 10:45 AM Ek Esawi <esawiek using gmail.com> wrote:
>>
>> Thank you. Sorry i forgot to turn off the html
>>
>> Below is a sample of my data. My original data frame has over 10,000 rows.
>> I want to check each element on my data frame column B
>> (MyDF$B) to see if it contains any element(s) of MYList. if os, change
>> the value of MyDF$C to the name of the vector of the list that has
>> match(s).
>>
>> I solved this via loops and if statements, using &in&  but I am hoping for
>> a more compact solution using the apply family functions. I tried something like
>> this but did not work.
>>
>> lapply(strsplit(MyDF$B," "),function(x) lapply(MyList,function(y)  if(sum(y
>> %in% x)>0,x$Code==y[[1]]))
>>
>> Thanks in advance--EK
>>
>> Sample data
>> MyList <- list(X=c("a","ba","cc"),Y=c("abs","aa","BA","BB"),z=c("ab","bb","xy","zy","gh"))
>> MyDF <- data.frame(A=c(1,2,3,4,5),B=c("aa ab ac","bb bc bd","cc
>> cf","dd","ee"), C= c(0,0,0,0,0), stringsAsFactors = FALSE)
>>
>> > MyDF
>>
>>     A     B      C
>> 1 1 aa ab ac  0
>> 2 2 bb bc bd  0
>> 3 3    cc cf     0
>> 4 4       dd     0
>> 5 5       ee     0
>>
>> > MyList
>>
>> $X
>> [1] "a"  "ba" "cc"
>>
>> $Y
>> [1] "abs" "aa"  "BA"  "BB"
>>
>> $z
>> [1] "ab" "bb" "xy" "zy" "gh"
>>
>>
>> Desired results.
>>
>> > MyDF
>>
>>    A     B        C
>> 1 1 aa ab ac Y
>> 2 2 bb bc bd Y
>> 3 3    cc cf    X
>> 4 4       dd     0
>> 5 5       ee     0
>>
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