INFORMATION PROCESSING APPARATUS AND COMPUTATIONAL METHOD

A storage unit stores a compressed matrix obtained by removing elements with zero values from a coefficient matrix and compressing the coefficient matrix in a direction that reduces the number of columns. A computing unit obtains a row group including a plurality of rows from the U-th row (U is an integer of one or greater) to the V-th row (V is an integer greater than U) from the compressed matrix, reorders elements within each row of the row group so as to collectively place first elements of the row group corresponding to elements belonging to columns different from the U-th to V-th columns of the coefficient matrix, in the same columns of the compressed matrix, and in an operation using the compressed matrix, performs operations respectively on a plurality of first elements that are continuous in the column direction in the row group, using an SIMD instruction.