From: Walter Roberson on
Kevin wrote:

> opfname =
> '23-Apr-2010' '_' 'test' '.csv'
>
> ??? Error using ==> fopen
> Invalid filename.
>
> Error in ==> blpqui>pushbutton1_Callback at 171
> new_file=fopen(opfname,'w');

opfname isn't a file name, it is a cell array.

horzcat(opfname{:})

would create a file name out of the parts.