```
# NOT RUN {
<!-- %% Note that ./Xtrct-methods.Rd has the indexing ones -->
# }
# NOT RUN {
set.seed(101)
(a <- m <- Matrix(round(rnorm(7*4),2), nrow = 7))
a[] <- 2.2 # <<- replaces **every** entry
a
## as do these:
a[,] <- 3 ; a[TRUE,] <- 4
m[2, 3] <- 3.14 # simple number
m[3, 3:4]<- 3:4 # simple numeric of length 2
## sub matrix assignment:
m[-(4:7), 3:4] <- cbind(1,2:4) #-> upper right corner of 'm'
m[3:5, 2:3] <- 0
m[6:7, 1:2] <- Diagonal(2)
m
## rows or columns only:
m[1,] <- 10
m[,2] <- 1:7
m[-(1:6), ] <- 3:0 # not the first 6 rows, i.e. only the 7th
as(m, "sparseMatrix")
# }
```

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