[Matrix]: use file_io to read data for finding #cols.
[Matrix]: use file_io to read data for finding #cols.

icoming/FlashX,flashxio/FlashX,icoming/FlashX,flashxio/FlashX,icoming/FlashX,flashxio/FlashX,icoming/FlashX,flashxio/FlashX,icoming/FlashX,flashxio/FlashX,flashxio/FlashX