Functions to create list (layers) of multiband raster images (stack in the notation of raster package) and to coerce list of images to single multiband image (brick in the notation of raster package).
ursa_stack(...)ursa_brick(obj)
ursa_apply(obj, FUN, ...)
# S3 method for ursaRaster
as.list(x, ...)
# S3 method for ursaStack
unlist(x, recursive, use.names)
Object of class ursaRaster
or list of ursaRaster
objects. In function ursa_apply
argument "X
", which is passed to function lapply
.
Argument "FUN
", which is passed to function lapply
.
Not used. For consistency with generic function unlist
.
Not used. For consistency with generic function unlist
.
Denending of functions:
ursa_stack , as.list |
|
List of ursaRaster objects |
|
ursa_apply |
ursa_stack
, as.list
return object of class ursaStack
. It is a list, with class "ursaStack" attribute.
unlist
(for list of ursaRaster
objects), ursa_brick
return object of class ursaRaster
.
ursa_apply
returns object of class ursaStack
, if result is list of ursaRaster
objects, otherwise returns general list
.
There is no any verifications, that grids of ursaRaster
objects are the same.
as.list
(of ursaRaster
object(s)), ursa_stack
create list of ursaRaster
objects, where items of list are sinle-band images. If x
is ursaRaster
object, then list(x)
create a list of length one, which item is multiband image.
unlist
(for list of ursaRaster
objects), ursa_brick
create single multiband ursaRaster
object. There is an alternative way for unlisting the list of ursaRaster
: as.ursa
.
Raster stack is a way to group bands, for example, by units (degree Celsium, meters). Raster brick is a way to combine versalite images to the single multiband image, for example, for saving in file.
c
for ursaRaster
objects.
# NOT RUN {
session_grid(NULL)
a <- ursa_dummy(3)
print(a)
b1 <- ursa_stack(a[1:2],colorize(a[3],ramp=FALSE))
print(b1)
b2 <- as.list(a)
print(b2)
b3 <- list(a[1],a[2:3])
print(b3)
b31 <- lapply(b3,colorize,ramp=FALSE)
print(b31)
b32 <- ursa_apply(b3,colorize,ramp=FALSE,rev=TRUE)
print(b32)
s311 <- ursa_apply(b31,ursa_colortable)
print(s311)
s21 <- lapply(b2,global_mean)
print(s21)
s22 <- sapply(b2,global_mean)
print(s22)
s31 <- lapply(b3,global_mean)
print(s31)
s32 <- sapply(b3,global_mean)
print(s32)
c1 <- unlist(b1)
print(c1)
c2 <- unlist(b2)
print(c2)
c3 <- unlist(b3)
print(if (is.ursa(c3)) c3 else "broken object")
d3 <- as.ursa(b3)
print(if (is.ursa(d3)) d3 else "broken object")
# }
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