## Not run:
# # Make an example netCDF file with a given missing value. We will
# # then change the missing value in the file using ncvar_change_missval
#
# origMissVal <- -1.
# dimX <- ncdim_def( "X", "meters", 1:7 )
# varAlt <- ncvar_def( "Altitude", "km", dimX, origMissVal )
# ncnew <- nc_create( "transect.nc", varAlt )
# data <- c(10.,2.,NA,1.,7.,NA,8.)
# ncvar_put( ncnew, varAlt, data )
# nc_close(ncnew)
#
# # At this point, the actual data values in the netCDF
# # file will be: 10 2 -1 1 7 -1 8
# # because the "NA" values were filled with the missing
# # value, -1. Also, the missing_value attribute of variable
# # "varAlt" will be equal to -1.
#
# # Now change the missing value to something else. Remember
# # we have to open the file as writable to be able to change
# # the missing value on disk!
#
# newMissVal <- 999.9
# nc <- nc_open( "transect.nc", write=TRUE )
# varname <- "Altitude"
# data <- ncvar_get( nc, varname ) # data now has: 10., 2., NA, 1., 7., NA, 8.
# print(data)
# ncvar_change_missval( nc, varname, newMissVal )
# ncvar_put( nc, varname, data )
# nc_close(nc)
#
# # Now, the actual data values in the netCDF file will be:
# # 10 2 999.9 1 7 999.9 8
# # and the variables "missing_value" attributre will be 999.9
#
# # **NOTE** that we had to explicitly read in the data and write
# # it out again in order for the on-disk missing values in the
# # data array to change! The on-disk missing_value attribute for
# # the variable is set automatically by this function, but it is
# # up to you whether or not you want to read in all the existing
# # data and change the values to the new missing value.
# ## End(Not run)
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