Utilities (Matlab) for accessing Noxmedical, Noxturnal https://noxmedical.com/products/noxturnal-software/ data files .ndf. THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND... (MIT license)
Event files are SQLite format. You can use e.g. https://sqlitebrowser.org/ to read files.
Matlab reading and writing ndf.m. Incomplete reverse engineering of file format. You can download demonstration recordings from https://support.noxmedical.com/hc/en-us/sections/201822583-PG-Demonstration-Recordings.
1) Reading ndf
nox=ndf('') % dialog
nox=ndf('Pressure.ndf') % load data
datestr(nox.start)
2) Writing ndf. Provide complete ascii .header or needed fields
nox.Type='Sine100Hz-100uv';
nox.Unit='V' % default
nox.Label=nox.Type; % default
nox.Format='Int16' % default
nox.Offset=0; % default
nox.start=floor(now()*24*60*2)/(24*60*2);
nox.Scale=1e-6;
nox.SamplingRate=100;
t=1/nox.SamplingRate:1/nox.SamplingRate:90;
d=[]; % 1-100 Hz, 100 uV
for f=1:1:100,
d=[d sin(2*pi.*t*f)*100e-6];
end
nox.data=d; % create ndf file
ndf('Sine100Hz-100uV.ndf',nox);