Compare rows of a data frame with a matrix rows in R - r

Question

I have created a matrix like this:
> head(matrix)
Var1 Var2 Var3 Var4 Var5 Var6 Var7 Var8 Var9 Var10 Var11
[1,] "0" "0" "1" "0" "1" "1" "0" "0" "0" "0" "NA"
[2,] "1" "0" "1" "0" "1" "1" "0" "0" "0" "0" "NA"
[3,] "0" "1" "1" "0" "1" "1" "0" "0" "0" "0" "NA"
[4,] "1" "1" "1" "0" "1" "1" "0" "0" "0" "0" "NA"
[5,] "0" "0" "2" "0" "1" "1" "0" "0" "0" "0" "NA"
[6,] "1" "0" "2" "0" "1" "1" "0" "0" "0" "0" "NA"
Now, I want to compare the matrix above with the following data frame:
> head(df)
cod Var11 Var1 Var2 Var3 Var4 Var5 Var6 Var7 Var8 Var9 Var10 Var12
1 C000354 B 1 1 4 0 1 2 0 0 0 1 51520.72
2 C000404 A 1 0 1 0 4 4 0 0 1 1 21183.25
3 C000444 A 1 0 4 1 3 3 0 0 0 1 67504.74
4 C000480 A 1 1 2 0 2 3 0 0 1 1 26545.92
5 C000983 C 1 0 1 0 3 4 0 0 0 0 10379.37
6 C000985 C 1 0 3 1 3 4 0 0 0 0 18660.99
Matrix contains all possible combinations of the variables Var1 Var2 Var3 Var4 Var5 Var6 Var7 Var8 Var9 Var10, so basically when a row of df (only column from VAR1 to VAR10) match with a row of matrix and this row in df had a Var12>=90000, I would like it to be written "A" in corresponding column VAR11 of matrix.
I have tried with this:
for (i in 1 : nrow(matrix)) {
for (j in 1 : 10) {
ifelse(matrix[i,j]==df[,(j+2)]
&& df$Var12[] >= 90000,
matrix[i,"Var11"] <- "A",
matrix[i,"Var11"] <- "NA")
}
}
But this writes NA in all rows of matrix.
Does anyone know why this happen or how to solve it?
Thanks in advance.

Answer 1

I don't understand why you used 1:10 and j+2 in your loop.
#Some dummy data
col_to_match<-paste0("V",1:10)
set.seed(123)
mat <- cbind(matrix(sample(0:4, 100, replace=TRUE), ncol=10), "NA")
colnames(mat)<-c(col_to_match,"V11")
set.seed(123)
df<- data.frame("cod"=paste0("C",1:20), "V12"= runif(20,min=88000,max=95000))
set.seed(1)
df <- cbind(df, rbind(mat[3:10,col_to_match], matrix(sample(0:4, 120, replace=TRUE), ncol=10)) )
From the dummy data, we expect the rows of the matrix
c(3:10)[df[1:8,"V12"]>=90000] to match the dummy data. Those are rows 3 4 5 6 7 9 10.
Run the following to check for every row in matrix, find whether there are any matching rows in df, and whether the V12 value is greater than 90000.
for(i in 1:nrow(mat)){
hasMatch<-any(sapply(1:nrow(df), function(j) all( df[j,col_to_match] == mat[i, col_to_match] ) && df[j,"V12"]>=90000 ))
if(hasMatch) mat[i, "V11"]<-"A"
}
Output
> mat
V1 V2 V3 V4 V5 V6 V7 V8 V9 V10 V11
[1,] "1" "4" "4" "4" "0" "0" "3" "3" "1" "0" "NA"
[2,] "3" "2" "3" "4" "2" "2" "0" "3" "3" "3" "NA"
[3,] "2" "3" "3" "3" "2" "3" "1" "3" "2" "1" "A"
[4,] "4" "2" "4" "3" "1" "0" "1" "0" "3" "3" "A"
[5,] "4" "0" "3" "0" "0" "2" "4" "2" "0" "1" "A"
[6,] "0" "4" "3" "2" "0" "1" "2" "1" "2" "0" "A"
[7,] "2" "1" "2" "3" "1" "0" "4" "1" "4" "3" "A"
[8,] "4" "0" "2" "1" "2" "3" "4" "3" "4" "0" "NA"
[9,] "2" "1" "1" "1" "1" "4" "3" "1" "4" "2" "A"
[10,] "2" "4" "0" "1" "4" "1" "2" "0" "0" "2" "A"