How to find the row products for each row in an R data frame?

R ProgrammingServer Side ProgrammingProgramming

To find the row products for each row in an R data frame, we can use rowProds function of matrixStats package but we need to read the data frame as a matrix.

For Example, if we have a data frame called df then we can find the row products for each row in df by using the command given below −

rowProds(as.matrix(df))

Example 1

Following snippet creates a sample data frame −

x1<-rpois(20,5)
x2<-rpois(20,2)
x3<-rpois(20,1)
df1<-data.frame(x1,x2,x3)
df1

The following dataframe is created −

 x1 x2 x3
 1  3  1  4
 2  7  2  0
 3  2  4  1
 4  9  2  0
 5  4  2  2
 6  7  3  1
 7  5  2  2
 8  1  2  0
 9  4  1  2
10  4  1  0
11  8  2  0
12  6  2  2
13  6  0  2
14  6  3  1
15  4  2  0
16 10  4  1
17  8  0  0
18  5  4  0
19  6  3  0
20  2  2  0

To load the matrixStats package and to find the row products for data in df1 on the above created data frame, add the following code to the above snippet −

x1<-rpois(20,5)
x2<-rpois(20,2)
x3<-rpois(20,1)
df1<-data.frame(x1,x2,x3)
library(matrixStats)
df1$Row_Product_df1<-rowProds(as.matrix(df1))
df1

Output

If you execute all the above given snippets as a single program, it generates the following Output −

x1  x2  x3  Row_Product_df1
1   3  1   4               12
2   7  2   0                0
3   2  4   1                8
4   9  2   0                0
5   4  2   2               16
6   7  3   1               21
7   5  2   2               20
8   1  2   0                0
9   4  1   2                8
10  4  1   0                0
11  8  2   0                0
12  6  2   2               24
13  6  0   2                0
14  6  3   1               18
15  4  2   0                0
16 10  4   1               40
17  8  0   0                0
18  5  4   0                0
19  6  3   0                0
20  2  2   0                0

Example 2

Following snippet creates a sample data frame −

y1<-round(rnorm(20),0)
y2<-round(rnorm(20),0)
y3<-round(rnorm(20),0)
y4<-round(rnorm(20),0)
df2<-data.frame(y1,y2,y3,y4)
df2

The following dataframe is created −

y1  y2  y3 y4
 1  0  -1  0  -2
 2  0  -1 -1   0
 3  1   0  1   0
 4  0   0  0   0
 5  1  -1  1   2
 6  0   0 -1  -1
 7 -1   0 -1   0
 8  1   0 -1   0
 9 -2   0 -2   1
10  0   0  0   1
11 -2   1 -2   0
12  0   1  0  -1
13  3   0  0   1
14  1  -1  1  -2
15 -1   1  1  -1
16  1   1 -1   0
17  0   0 -1   0
18  2   0  2  -1
19  3   2  0  -1
20  1   0 -1  -1

To find the row products for data in df2 on the above created data frame, add the following code to the above snippet −

y1<-round(rnorm(20),0)
y2<-round(rnorm(20),0)
y3<-round(rnorm(20),0)
y4<-round(rnorm(20),0)
df2<-data.frame(y1,y2,y3,y4)
df2$Row_Product_df2<-rowProds(as.matrix(df2))
df2

Output

If you execute all the above given snippets as a single program, it generates the following Output −

y1  y2  y3  y4 Row_Product_df2
1   0  -1   0   -2              0
2   0  -1  -1    0              0
3   1   0   1    0              0
4   0   0   0    0              0
5   1  -1   1    2             -2
6   0   0  -1   -1              0
7  -1   0  -1    0              0
8   1   0  -1    0              0
9  -2   0  -2    1              0
10  0   0   0    1              0
11 -2   1  -2    0              0
12  0   1   0   -1              0
13  3   0   0    1              0
14  1  -1   1   -2              2
15 -1   1   1   -1              1
16  1   1  -1    0              0
17  0   0  -1    0              0
18  2   0   2   -1              0
19  3   2   0   -1              0
20  1   0  -1   -1              0
raja
Updated on 27-Oct-2021 11:26:13

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