`reclassify.Rd`

Reclassify values of a Raster* object. The function (re)classifies groups of values to other values. For example, all values between 1 and 10 become 1, and all values between 11 and 15 become 2 (see functions `subs`

and `cut`

for alternative approaches).

Reclassification is done with matrix `rcl`

, in the row order of the reclassify table. Thus, if there are overlapping ranges, the first time a number is within a range determines the reclassification value.

```
# S4 method for Raster
reclassify(x, rcl, filename='', include.lowest=FALSE, right=TRUE, ...)
```

- x
Raster* object

- rcl
matrix for reclassification. This matrix can have 3 or 2 columns.

In a

`3-column matrix`

the first two columns are "from" - "to" for the input values, and the third column "becomes" has the new value for that range. (You can also supply a vector that can be coerced into a n*3 matrix (with`byrow=TRUE`

)).A

`2-column matrix`

represents ("is", "becomes") which can be useful for integer values. In that case, the`right`

argument is automatically set to`NA`

- filename
character. Output filename (optional)

- include.lowest
logical, indicating if a value equal to the lowest value in rcl (or highest value in the second column, for right = FALSE) should be included. The default is

`FALSE`

- right
logical, indicating if the intervals should be closed on the right (and open on the left) or vice versa. The default is

`TRUE`

. A special case is to use right=NA. In this case both the left and right intervals are open- ...
additional arguments as for

`writeRaster`

Raster* object

```
r <- raster(ncols=36, nrows=18)
values(r) <- runif(ncell(r))
# reclassify the values into three groups
# all values > 0 and <= 0.25 become 1, etc.
m <- c(0, 0.25, 1, 0.25, 0.5, 2, 0.5, 1, 3)
rclmat <- matrix(m, ncol=3, byrow=TRUE)
rc <- reclassify(r, rclmat)
# for values >= 0 (instead of > 0), do
rc <- reclassify(r, rclmat, include.lowest=TRUE)
# equivalent to
rc <- reclassify(r, c(-Inf,0.25,1, 0.25,0.5,2, 0.5,Inf,3))
```