nc_write: Write a data.frame containing data on a grid as a netCDF file
In jiho/ncdf4helpers: Helpers to easily read from and write NetCDF files

Description Usage Arguments Examples

View source: R/nc_write.R

Write a data.frame containing data on a grid as a netCDF file

1 2	nc_write(d, file, dimensions, variables = NULL, units = NULL, attributes = NULL, global.attributes = NULL, missval = -99999)

`d`	data.frame containing coordinates (along dimensions) and variables
`file`	output file path
`dimensions`	names or indexes of columns in d representing the data dimensions
`variables`	names or indexes of columns in d represented the measured variables. If NULL, all columns which are not dimensions are considered as variables
`units`	named vector or list containing character strings which specify the units of dimensions and variables. The names must be those of columns in d. Defaults to no unit
`attributes`	list of lists containing attributes (second-level lists) for each dimension and variable (first level list). The list must be named with names which are dimensions or variables (i.e. columns of d). Each second-level list is also a named list which stores attributes as key/value pairs, where the key is the name of the element of the list and the value is the content of that element
`global.attributes`	list of key/value pairs similar to the variables/dimensions attributes above but stored as global attributes of the file
`missval`	value used to code missing values in the netCDF file

# create data, on a grid, stored in a data.frame
x <- 1:3
y <- 1:2
d <- expand.grid(x=x, y=y)
d$V1 <- runif(nrow(d))
d$V2 <- rnorm(nrow(d), mean=90)

file_name <- tempfile()
nc_write(d, file=file_name,
  # dimensions are specified, variables are not
  # => variables are all other columns (V1 and V2)
  dimensions = c("x", "y"),
  # units are a named list
  units = c(x="m", y="m", V1="degrees Celsius", V2="volts"),
  # variables attributes are specified as a list of lists
  attributes = list(
    x = list(long_name="x coordinate", standard_name="x"),  
    y = list(long_name="y coordinate", standard_name="y"),  
    V1 = list(long_name="Temperature at surface", standard_name="temp"),  
    V2 = list(long_name="Tension between poles", standard_name="tension") 
  ),
  # global attributes are not associated with any particular variable
  global.attributes = list(
    author = "Pr Foobar",
    convention = "CF-1.2",
    date_created = "2014-06-19"
  )
)