[R] Comparing the components of a data frame without levels interfering

[Petr PIKAL]

Hi


> *Bottom Line: How can I compare the individual components of two data 
frames
> with different row lengths without the levels interfering?*
> 
> Example: I have two data frames to those respectively named 'dfCity' and
> 'dfState' that have the following output:
> 
> dfCity
> 
>      Name       City 
> 1    Bill        Detroit 
> 2    Jody      Chicago
> 3    Frank    Memphis 
> 4    Ron       Houston 
> 
> dfState
> 
>      Name       State
> 1    Bill        Michigan
> 2    Frank    Tennessee 
> 
> I have an if statement that is trying to compare the individual's names 
and
> combine the data from the two different data frames to produce some 
output: 
> 
> for(j in 1:length(row.names(dfState))){
>          for(k in 1:length(row.names(dfCity))){
>             if(dfCity[k,1] == dfState[j,1]){
>                cityState <- paste(dfCity[k,2], ", ", dfState[j,2], sep= 
"") 
>                print(dfCity[1, j], " is from ", cityState)
>             }
>          }
>       }

What about first merge two data frames

mergedDF <- merge(dfCity, dfState, all=TRUE)

and after that you can do

cityState <- paste(mergedDF$City, ", ", mergedDF$State, sep= "")

or anything you want.

Regards
Petr

> 
> However, when I run it I get the error /Error in Ops.factor(dfState[2, 
1],
> dfCity[4, 1]) : level sets of factors are different/ due to the levels 
in
> the data frames. *How can I compare the individual components of the 
data
> frame without the levels interfering? *
> 
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> 
components-of-a-data-frame-without-levels-interfering-tp3900502p3900502.html
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