| 1 | |
| 2 | #data: matrix of double or connection |
| 3 | serialize = function(data, file, type, nb_per_chunk) |
| 4 | { |
| 5 | bin_data = file(file, "ab") |
| 6 | #write data length on first call |
| 7 | nbytes = ifelse(type=="double",8,4) |
| 8 | first_write = FALSE |
| 9 | if (file.info(file)$size == 0) |
| 10 | { |
| 11 | #number of items always on 8 bytes |
| 12 | writeBin(0L, bin_data, size=8) #,endian="little") |
| 13 | first_write = TRUE |
| 14 | } |
| 15 | if (is.matrix(data)) |
| 16 | { |
| 17 | writeBin(t(data), bin_data, size=nbytes) |
| 18 | data_length = ncol(data) |
| 19 | } |
| 20 | else #if (is(data, "connection")) |
| 21 | { |
| 22 | if (first_write) |
| 23 | { |
| 24 | data_line = scan(data, double(), sep=",", nlines=1) |
| 25 | writeBin(data_line, bin_data, size=nbytes) |
| 26 | data_length = length(data_line) |
| 27 | } |
| 28 | repeat |
| 29 | { |
| 30 | data_chunk = scan(data, double(), sep=",", nlines=nb_per_chunk) |
| 31 | if (length(data_chunk)==0) |
| 32 | break |
| 33 | writeBin(data_chunk, bin_data, size=nbytes) |
| 34 | } |
| 35 | } |
| 36 | if (first_write) |
| 37 | { |
| 38 | #ecrire file_size-1 / (nbytes*nbWritten) en 0 dans bin_data ! ignored == file_size |
| 39 | ignored = seek(bin_data, 0) |
| 40 | writeBin(data_length, bin_data, size=8) |
| 41 | } |
| 42 | close(bin_data) |
| 43 | } |
| 44 | |
| 45 | #TODO: read in binary file, always same structure |
| 46 | getDataFromFile(indices, file, type) |
| 47 | { |
| 48 | bin_data = file(file, "rb") |
| 49 | nbytes = ifelse(type=="double",8,4) |
| 50 | data_length = readBin(bin_data,"double",1,nbytes) #,endian="little") |
| 51 | t(sapply(indices, function(i) readBin(bin_data,"double",n=data_length,size=nbytes))) |
| 52 | } |