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FiffRawDir

Namespace: FIFFLIB  ·  Library: FIFF Library

#include <fiff/fiff_raw_dir.h>

class FIFFLIB::FiffRawDir

Per-buffer raw-data directory entry: data kind, first sample, sample count, on-disk tag position.

One entry per FIFF_DATA_BUFFER tag. The (first, nsamp) fields let FiffRawData::read_segment binary-search the directory for the buffers that cover a requested sample window and stream them in without rescanning the file.

src/examples/ex_fiff_structure/main.cpp
// The raw data directory: one FiffRawDir per data buffer, each pointing at its FiffDirEntry in the file.
int samples = 0;
for (const FiffRawDir& buffer : raw.rawdir)
    samples += buffer.nsamp;
const FiffDirEntry::SPtr firstBuffer = raw.rawdir.first().ent;

Public Methods​

FiffRawDir()​

Default constructor.

FiffRawDir(p_FiffRawDir)​

Copy constructor.

Parameters:

  • p_FiffRawDir : const FiffRawDir & Raw directory entry which should be copied.

operator=(other)​

Copy assignment.

Every member has value semantics, so the compiler-generated member-wise assignment is correct. It is declared explicitly because declaring a copy constructor and/or a destructor deprecates the implicitly generated one.

Parameters:

  • other : const FiffRawDir & Object to assign from.

Returns:

~FiffRawDir()​

Destroys the raw Directory entry.

Example​

Used in examples​

ex_fiff_structure​

FIFF library: fixed-length epochs, CTF compensation, the file directory and raw buffers, and handing.

src/examples/ex_fiff_structure/main.cpp, line 109
// The raw data directory: one FiffRawDir per data buffer, each pointing at its FiffDirEntry in the file.
int samples = 0;
for (const FiffRawDir& buffer : raw.rawdir)
    samples += buffer.nsamp;
const FiffDirEntry::SPtr firstBuffer = raw.rawdir.first().ent;
// mne.io.read_raw_fif: 2 buffers, 6007 samples from first_samp 12900; fiff_open lists 640 directory entries
ok &= expect(raw.rawdir.size() == 2 && samples == 6007 && raw.rawdir.first().first == 12900 && firstBuffer->kind == FIFF_DATA_BUFFER,
             "FiffRawDir/FiffDirEntry: 2 data buffers cover the 6007 samples from sample 12900");

Authors of this file​