impz                 package:signal                 R Documentation

_I_m_p_u_l_s_e-_r_e_s_p_o_n_s_e _c_h_a_r_a_c_t_e_r_i_s_t_i_c_s

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

     Impulse-response characteristics of a discrete filter.

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

     ## Default S3 method:
     impz(filt, a = 1, n = NULL, Fs = 1, ...)

     ## S3 method for class 'Arma':
     impz(filt, ...)

     ## S3 method for class 'Ma':
     impz(filt, ...)

     ## S3 method for class 'impz':
     plot(x, ...)

     ## S3 method for class 'impz':
     print(x, ...)

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

    filt: for the default case, the moving-average coefficients of an
          ARMA model or filter. Generically, 'filt' specifies an
          arbitrary model or filter operation.

       a: the autoregressive (recursive) coefficients of an ARMA
          filter. 

       n: number of points at which to evaluate the frequency response. 

      Fs: sampling frequency in Hz. If not specified, the frequencies
          are in per unit. 

     ...: for methods of 'impz', arguments are passed to the default
          method. For 'plot.impz', additional arguments are passed
          through to 'plot'. 

       x: object to be plotted. 

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

     When results of 'impz' are printed, the impulse response will be
     plotted. As with 'lattice' plots, automatic printing does not work
     inside loops and function calls, so explicit calls to 'print' or
     'plot' are needed there.

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

     For 'impz', a list of class 'impz' with items: 

      x : impulse response signal. 

      t : time.

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

     Original Octave version by Kurt Hornik and John W. Eaton.
     Conversion to R by Tom Short.

_R_e_f_e_r_e_n_c_e_s:

     <URL: http://en.wikipedia.org/wiki/Impulse_response>

     Octave Forge <URL: http://octave.sf.net>

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

     'filter', 'freqz', 'zplane'

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

     bt = butter(5, .3)
     impz(bt)
     impz(ellip(5, .5, 30, .3))

