An apparatus for processing a plurality of data sets is disclosed, wherein one data set of the plurality of data sets includes N components and has a data type of one of a scalar type and a vector type, wherein N is a positive integer number. The apparatus includes a memory module and a data accessing module. The memory module comprises N memory units configured to store the plurality of data sets. The data accessing module is configured to write the data set into the memory module according to a write data index corresponding to the data set and one of a first writing mapping information and a second writing mapping information, wherein the first writing mapping information is employed when the data type is one of the scalar and the vector type and the second writing mapping information is employed when the data type is the other of the scalar and the vector type.