```
# NOT RUN {
# A red gradient
as.raster(matrix(hcl(0, 80, seq(50, 80, 10)),
nrow = 4, ncol = 5))
# Vectors are 1-column matrices ...
# character vectors are color names ...
as.raster(hcl(0, 80, seq(50, 80, 10)))
# numeric vectors are greyscale ...
as.raster(1:5, max = 5)
# logical vectors are black and white ...
as.raster(1:10 %% 2 == 0)
# ... unless nrow/ncol are supplied ...
as.raster(1:10 %% 2 == 0, nrow = 1)
# Matrix can also be logical or numeric (or raw) ...
as.raster(matrix(c(TRUE, FALSE), nrow = 3, ncol = 2))
as.raster(matrix(1:3/4, nrow = 3, ncol = 4))
# An array can be 3-plane numeric (R, G, B planes) ...
as.raster(array(c(0:1, rep(0.5, 4)), c(2, 1, 3)))
# ... or 4-plane numeric (R, G, B, A planes)
as.raster(array(c(0:1, rep(0.5, 6)), c(2, 1, 4)))
# subsetting
r <- as.raster(matrix(colors()[1:100], ncol = 10))
r[, 2]
r[2:4, 2:5]
# assigning to subset
r[2:4, 2:5] <- "white"
# comparison
r == "white"
# }
# NOT RUN {
<!-- % end{tests} -->
# }
```

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