itsArith                 package:its                 R Documentation

_A_r_i_t_h_m_e_t_i_c _M_e_t_h_o_d_s _f_o_r _I_r_r_e_g_u_l_a_r _T_i_m_e-_S_e_r_i_e_s _O_b_j_e_c_t_s

_D_e_s_c_r_i_p_t_i_o_n:

     Arithmetic methods for objects of class '"its"'.

_U_s_a_g_e:

          x + y
          x - y
          x * y
          x / y
          x ^ y
          x 
          x 

_A_r_g_u_m_e_n_t_s:

     x,y: an object of class '"its"'

_D_e_t_a_i_l_s:

     The arithmetic operators return numeric vectors containing the
     result of the  element-by-element operations.  The dates of the
     arguments are matched and the intersection of the dates is
     returned.

     Note that the matrix multiplication operator,  and the result of a
     matrix multiplication is a matrix, not an '"its"'. The resulting
     matrix can be converted back to its using the function its()  -
     see examples.

_V_a_l_u_e:

     The returned object is an object of class '"its"', having the same
     number of columns as the two arguments, however, the number of
     rows will be the length of the intersection of the dates of the
     two arguments.

_A_u_t_h_o_r(_s):

     Giles Heywood

_S_e_e _A_l_s_o:

     'ts', 'POSIXct', 'itsFile', 'itsLags' 'itsJoin' 'itsTimes'
     'itsSubset' 'itsFin' 'itsDisp' 'itsInfo' 'itsCumdif' 'itsInterp'

_E_x_a_m_p_l_e_s:

     b <- newIts(1:30,ncol=3)
     c <- newIts(1:10,ncol=3)[1:5,]
     b+c
     b+b-2*b
     b/b
     b%*%diag(ncol(b))
     its(b%*%diag(ncol(b))) 

