Here is a quick example of how to add extra rows to a data frame in R. I’m using the colMeans() function to calculate a new value I want to add. First loading the data into a data frame with as.data.frame(). Then doing a simple for loop going from one to ten. Lastly adding the extra row by using the nrow plus one.

```
df <- as.data.frame(id_mat[1:2000, -1])
for (i in seq(1, 10, 1)) {
df[(nrow(df) + 1),] = colMeans(id_mat[i:(i+199), -1])
}
```

Take a look at https://spacetech.dk/how-to-calculate-mean-for-multiple-columns-in-r.html if you want to see how the colMeans() function works.