# Matlab file format

The ecg-kit allows users to use Matlab native format to store and access recordings. For using it, ensure that your mat file follows these naming convention:

> 1. Your signal variable must be named `'sig', 'signal' or 'ECG'`. Remember that the signals or leads must be placed column-wise, that is `signal = [ lead1 lead2 lead3 ... lead_nsig]`.
> 2. The header or signal information must be stored in a struct named `'header', 'heasig' or 'hea'`.
> 3. (Optional) In case of including annotations or QRS detections, be sure to be a struct named `'ann', 'annotations' or 'qrs'` and which includes the fields described for the MIT format in Physionet.
>    - time: the time within the recording (recorded in the annotation file as the sample number of the sample to which the annotation “points”)
>    - anntyp [sic]: a numeric annotation code (see ecgcodes.h for definitions)
>    - subtyp [sic], chan, num: three small integers (between -128 to 127) that specify context-dependent attributes (see the documentation for each database for details)
>    - aux: a free text string

See the `ecg-kit\common\matformat_definitions.m` for more details.