Re-tested the inner product function. 

parallelled version slower than MATLAB's transpose mtimes.

serial version is not too slower than parallelled version, about 2x
slower than MATLAB's transpose mtimes method.

Signed-off-by: Yimin <zhongym8903@gmail.com>
compared performance on x'Ax, better use MATLAB's function.

Signed-off-by: Yimin <zhongym8903@gmail.com>
minor changes to functions.

Signed-off-by: Yimin <zhongym8903@gmail.com>