buffer2(i+imax*(3-1)) = buffer2(i+imax*(3-1)) + buffer1(1+(i-1)*kmax) * sphi_b(1,3+s_offset_b1)
buffer2(i+imax*(5-1)) = buffer2(i+imax*(5-1)) + buffer1(1+(i-1)*kmax) * sphi_b(1,5+s_offset_b1)
buffer2(i+imax*(1-1)) = buffer2(i+imax*(1-1)) + buffer1(2+(i-1)*kmax) * sphi_b(2,1+s_offset_b1)
buffer2(i+imax*(4-1)) = buffer2(i+imax*(4-1)) + buffer1(3+(i-1)*kmax) * sphi_b(3,4+s_offset_b1)
buffer2(i+imax*(3-1)) = buffer2(i+imax*(3-1)) + buffer1(4+(i-1)*kmax) * sphi_b(4,3+s_offset_b1)
buffer2(i+imax*(5-1)) = buffer2(i+imax*(5-1)) + buffer1(4+(i-1)*kmax) * sphi_b(4,5+s_offset_b1)
buffer2(i+imax*(2-1)) = buffer2(i+imax*(2-1)) + buffer1(5+(i-1)*kmax) * sphi_b(5,2+s_offset_b1)
buffer2(i+imax*(3-1)) = buffer2(i+imax*(3-1)) + buffer1(6+(i-1)*kmax) * sphi_b(6,3+s_offset_b1)
