write.magpie {magclass}

Write MAgPIE-object to file

Description

Writes a magpie object to a file. The file type is determined by the filename extension. The written file can be read again using read.magpie.

Usage

write.magpie(
  x,
  file_name,
  file_folder = "",
  file_type = NULL,
  append = FALSE,
  comment = NULL,
  comment.char = "*",
  mode = NULL,
  zname = "time",
  ...
)

Arguments

x

a magclass object. An exception is that formats written via the raster package (currently "nc", "asc", "grd" and "tif") also accept RasterBrick objects which have been previously created from a magclass object via as.RasterBrick)

file_name

file name including file ending (wildcards are supported). Optionally also the full path can be specified here (instead of splitting it to file_name and file_folder)

file_folder

folder the file should be written to (alternatively you can also specify the full path in file_name - wildcards are supported)

file_type

Format the data should be stored as. If file_type=NULL the file ending of the file_name is used as format. See detailed description for a list of available file types. Please be aware that the file_name is independent of the file_type you choose here, so no additional file ending will be added!

append

Decides whether an existing file should be overwritten (FALSE) or the data should be added to it (TRUE). Append = TRUE only works if the existing data can be combined with the new data using the mbind function

comment

Vector of strings: Optional comment giving additional information about the data. If different to NULL this will overwrite the content of attr(x,"comment")

comment.char

character: a character vector of length one containing a single character or an empty string. Use "" to turn off the interpretation of comments altogether.

mode

File permissions the file should be written with as 3-digit number (e.g. "777" means full access for user, group and all, "750" means full access for user, read access for group and no acess for anybody else). Set to NULL system defaults will be used. Access codes are identical to the codes used in unix function chmod.

zname

name of the time variable for raster files like nc, asc, grd and tif

...

additional arguments passed to specific write functions

Details

This function supports writing the following file types:

• "cs2" is the new standard format for cellular data with or without header and the first columns (year,regiospatial) or only (regiospatial)

• "cs2b" is identical to "cs2" except that it will suppress the data name if it has only 1 element in the data dimension.

• "csv" is the standard format for regional data with or without header and the first columns (year,region,cellnumber) or only (region,cellnumber)

• "cs3" is another csv format which is specifically designed for multidimensional data for usage in GAMS.

• "cs4" alternative multidimensional format compatible to GAMS, in contrast to cs3 it can also handle sparse data

• "csvr", "cs2r", "cs3r", "cs4r" which are the same formats as the ones previously explained with the only difference that they have a REMIND compatible format

• "cs5" a more generalized version of cs4

• "rds" is an R-default format for storing R objects

• "m" (magpie) and "mz" (magpie zipped) are new formats developed to allow a less storage intensive management of MAgPIE-data. The only difference between both formats is that .mz is gzipped whereas .m is not compressed. So .mz needs less memory, whereas .m might have a higher compatibility to other languages

• "asc" is the ASCII grid format. It can only be applied for gridded data and writes one file per year per data column. In the case that more than one year and data column is supplied several files are written with the structure filename_year_datacolumn.asc

• "tif" is the GEOtiff format for gridded data.

• "grd" is the native raster format for gridded data.

• "nc" is the netCDF format for gridded data.

Note

The binary MAgPIE formats .m and .mz have the following content/structure (you only have to care for that if you want to implement read.magpie/write.magpie functions in other languages):

[ FileFormatVersion | Current file format version number (currently 6) | integer | 2 Byte ]
[ nchar_comment | Number of character bytes of the file comment | integer | 4 Byte ]
[ nbyte_metadata | Number of bytes of the serialized metadata (currently = 0) | integer | 4 Byte ]
[ nchar_sets | Number of characters bytes of all regionnames + 2 delimiter | integer | 2 Byte]
[ nyears | Number of years | integer | 2 Byte ]
[ yearList | All years of the dataset (0, if year is not present) | integer | 2*nyears Byte ]
[ ncells | Number of cells | integer | 4 Byte ]
[ nchar_cell | Number of characters bytes of all regionnames + (nreg-1) for delimiters | integer | 4 Byte ]
[ cells | Cell names saved as cell1\cell2 (\n is the delimiter) | character | 1*nchar_cell Byte ]
[ nelem | Total number of data elements | integer | 4 Byte ]
[ nchar_data | Number of char. bytes of all datanames + (ndata - 1) for delimiters | integer | 4 Byte ]
[ datanames | Names saved in the format data1\ndata2 (\n as del.) | character | 1*nchar_data Byte ]
[ data | Data of the MAgPIE array in vectorized form | numeric | 4*nelem Byte ]
[ comment | Comment with additional information about the data | character | 1*nchar_comment Byte ]
[ sets | Set names with \n as delimiter | character | 1*nchar_sets Byte]
[ metadata | serialized metadata information (currently not in use) | bytes | 1*nbyte_metadata Byte]

Author(s)

Jan Philipp Dietrich, Stephen Bi, Florian Humpenoeder, Pascal Sauer

See Also

"magpie", read.magpie,mbind

Examples

pop <- maxample("pop")
path <- tempfile(fileext = ".mz")
write.magpie(pop, path)
pop2 <- read.magpie(path)