classRaster_is.na: 'No data' values for raster images.

In ursa: Non-Interactive Spatial Tools for Raster Processing and Visualization

‘No data’ values for raster images.

Description

The "Extract" function is.na creates mask for each band. In this mask value 1L corresponds to NA value in the source image, and value NA corresponds non-missing values in the source image. The "Replacement" function is.na<- assigns numerical value for cells with ‘no data’ value.

Usage

## S3 method for class 'ursaRaster'
is.na(x)

## S3 method for class 'ursaRaster'
is.infinite(x)

## S3 method for class 'ursaRaster'
is.nan(x)

## S3 replacement method for class 'ursaRaster'
is.na(x) <- value

Arguments

x	Object of class ursaRaster
value	Numeric.

Details

These functions are corresponded to local operators of map algebra.

Value

"Extract" functions is.na, is.infinite, is.nan return object of class ursaRaster.

"Replacement" function is.na<- modifies object of class ursaRaster.

Author(s)

Nikita Platonov [e-mail]

Examples

session_grid(NULL)
session_grid(regrid(mul=1/4))
a <- ursa_dummy(nband=2,min=0,max=100)
print(a)
print(is.na(a))
a2 <- ursa_new(nband=2)
print(a2)
print(is.na(a2))
a3 <- a
a3[a3<30 | a3>70] <- NA
print(a3)
print(is.na(a3))
is.na(a3) <- 200
print(a3)

ursa documentation built on Sept. 30, 2024, 9:35 a.m.