Find Match of two data frames and rewrite the answer as data frame

Question

i have two data frames which are cleaned and merged as a single csv file , the data frames are like this

  **Source                         Master**

 chang         


        

Answer 1

If you want to check the Master.Names only against the first word in Names, this could do the trick:

Names$Mast <- NA
for(i in seq_len(nrow(Names))) 
    Names$Mast[i] <- grep(toupper(x = strsplit(Names[i,1]," ")[[1]][1]), Master.Names$V1,value=TRUE)

Edit

Using sapply instead of a loop could gain you some speed:

Names$Mast <- sapply(Names$V1, function(x) {
    grep(toupper(x = strsplit(x," ")[[1]][1]), Master.Names$V1,value=TRUE)
})

Results

> Names
                        V1                            Mast
1 chang chun petrochemical                CHANG CHUN GROUP
2      chang chun plastics                CHANG CHUN GROUP
3            church dwight        CHURCH AND DWIGHT CO INC
4   citrix systems pacific CITRIX SYSTEMS ASIA PACIFIC P L

Data

Master.Names <- read.csv(text="CHANG CHUN GROUP
CHURCH AND DWIGHT CO INC
CITRIX SYSTEMS ASIA PACIFIC P L
CNH INDUSTRIAL N.V", header=FALSE)

Names <- read.csv(text="chang chun petrochemical
chang chun plastics     
church dwight          
citrix systems pacific", header=FALSE)