Trims rows and columns from the edges of a surface matrix that contain missing values only.
Arguments
- x3p
x3p object
- ratio
ratio between zero and one, indicating the percent of values that need to be missing in each row and column, for the row or column to be removed
Value
x3p object of the same or smaller dimension where missing values are removed from the boundaries
Examples
logo <- x3p_read(system.file("csafe-logo.x3p", package="x3ptools"))
logo$surface.matrix[logo$surface.matrix == median(logo$surface.matrix)] <- NA
x3p_trim_na(logo) # reduced to dimension: 668 by 268
#> x3p object
#> Instrument: N/A
#> size (width x height): 669 x 269 in pixel
#> resolution: 6.4500e-07 x 6.4500e-07
#> Creator: Heike Hofmann, CSAFE
#> Comment: image rendered from the CSAFE logo ; cropped from location ( 36 , 74 )