write metadata and events in c3d (matlab)

[Jana Peckedrath]

Hallo everybody,

I have the problem, that i want to set metadat to a new  Acquisition.
I already tried this code but it doesnt work. Maybe anybody can help me...

I just want to edit a metadata with the description (Age, Height, Mass, Sex) and another field with frequency and one with events. Events should be subdivided into 4.

------------------------------------------- code ------------------------------------------

metadat = struct ('Age', Age, 'Height', Height, 'Mass', Mass, 'Sex', Sex);

info         = btkMetaDataInfo('Char',metadat,4);

--> i got this Error:

Error using btkAppendMetaData
The field 'format' must be set by cell of strings or an array of numerical (double) values.

for the events a have a struct with all events:
events.TO_l       = [1; 45;103];
events.TO_r      = [28;84];
events.TD_l       = [32; 68];
events.TD_r       = [59;115];

i need your help!