Comparison: Relational operators for antsImage
In stnava/itkImageR: Examples using Rcpp to interface R and ITK

Description Usage Arguments Details Value Author(s) Examples

Relational operators to compare pixel values of an antsImage with a scalar value within a given antsRegion.

img == value
img != value
img <= value
img >= value
img < value
img > value

  or use lists

img == lst
img != lst
img <= lst
img >= lst
img < lst
img > lst

`img`	Image object of S4 class 'antsImage' to be indexed.
`value`	Scalar `numeric` to be compared to the pixel values.
`lst`	`list` of named arguments containing names 'value' and 'region'. `lst$value` is used as 'value' and `lst$region` is used as the `antsRegion` within the image for comparison.

img == value: Image-region considered is the largest-possible-region( entire image ) of the image.

logical vector of dimensions equal to that of 'region' considered – Success ; NA – Failure

Shrinidhi KL

## Not run: 
# compare all the values in the region starting at index 'c(1,1,1)' with size 'c(10,10,10)' with value '20' ;
# here the logical vector 'vect' will have dimensions '10*10*10'
reg = new( "antsRegion" , index = c(1,1,1) , size = c(10,10,10) )
vect = ( img = list( value = 20 , region = reg ) )
# compare all the pixels in the image with value '30' ;
# here the logical vector 'vect' will have dimensions of the image
vect = ( img == 30 )

## End(Not run)