Generic functiont to read large blocks of accelerometer data

The function is used by g.getmeta and g.calibrate to read large blocks of the accelerometer file, which are processed and then deleted from memory. This is needed for memory management.

Usage

g.readaccfile(filename, blocksize, blocknumber, filequality,
                           decn, ws, PreviousEndPage = 1, inspectfileobject = c(),
                           PreviousLastValue = c(0,0,1), PreviousLastTime = NULL,
                           params_rawdata = c(), params_general = c(), ...)

Arguments

filename: filename
blocksize: Size of blocks (in file pages) to be read
blocknumber: Block number relative to start of file
filequality: Single row dataframe with columns: filetooshort, filecorrupt, and filedoesnotholdday. All with the value TRUE or FALSE
decn: Character with a dot or a comma, used for interpretting samplefrequency in the file header. decn is derived with g.dotorcomma
ws: Larger windowsize for non-detection, see documentation g.part2
PreviousEndPage: Page number on which previous block ended (automatically assigned within g.getmeta and g.calibrate).
inspectfileobject: Output from the function g.inspectfile.
PreviousLastValue: Automatically identified last value in previous chunk of data read.
PreviousLastTime: Automatically identified last timestamp in previous chunk of data read.
params_rawdata: See g.part1
params_general: See g.part1
...: Any input arguments needed for function read.myacc.csv if you are working with a non-standard csv formatted files. Furter, any argument used in the previous version of g.readaccfile, which will now be used to overrule the arguments specified with the parameter objects.

Value

P Block object extracted from file with format specific to accelerometer brand
filequality Same as in function arguments
switchoffLD Boolean to indicate whether it is worth continueing to read the next block of data or not
endpage Page number on which blocked ends, this will be used as input for argument PreviousEndPage when reading the next block.

Author

Vincent T van Hees <v.vanhees@accelting.com>

Examples

  if (FALSE) {
    filequality = data.frame(filetooshort = FALSE, filecorrupt = FALSE,
    filedoesnotholdday = FALSE)
    output = g.readaccfile(filename = "C:/myfile.bin", 
    blocksize = 20000, blocknumber = 1,
    selectdaysfile = c(), filequality = filequality,
    decn = ".", dayborder = 0, PreviousEndPage = c()) 
  }