tfwindow               package:tframe               R Documentation

_T_r_u_n_c_a_t_e _a _T_i_m_e _S_e_r_i_e_s

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

     Truncate a time series object to a time window.

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

         tfwindow(x, ...)
         tfwindow(x, start.=NULL, end.=NULL, tf=NULL, warn=TRUE)
         tfwindow(x, start.=NULL, end.=NULL, tf=NULL, warn=TRUE)


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

       x: A time series object.

     ...: arguments to be passed to other methods.

  start.: A start date of a format compatible with the time series

    end.: An end date of a format compatible with the time series

      tf: A tframe or tframed object

    warn: A logical indicating if warning should be produced

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

     If `start.' or `end.' are omitted and `tf' is specified then the
     start or end is taken from the `tf' object. For ts class objects
     this function calls window but makes more effort to  preserve
     `seriesNames' if `x' has them.  It also supports the optional
     argument `warn' to suppress warning messages. Frequently it is
     convenient to write code which always  truncates to a window
     without first checking if the data is already within  the window.
     Since window produces a warning in this situation, the optional 
     argument is frequently useful when tfwindow is used by other code.
     In Splus `tfwindow' also corrects for some bugs in older versions 
     of code{window}.

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

     A time series object similar to x, but typically spanning a
     shorter time period.

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

       z <- ts(matrix(rnorm(24),24,1), start=c(1980,1), frequency=4)
       zz <- tfwindow(z, start=c(1982,2))
       zzz <- matrix(rnorm(24),24,1)
       tframe(zzz) <- tframe(z)
       tfwindow(zzz, tf=tframe(zz))

