pfnc                 package:hpower                 R Documentation

_N_o_n_c_e_n_t_r_a_l _F _D_i_s_t_r_i_b_u_t_i_o_n

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

     Using the first terms in the series expansion 26.6.20 in
     Abramowitz and Stegun, compute the probability integral of the
     noncentral F distribution.

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

     pfnc(q, df1, df2, lm, iprec=c(6))

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

       q: vector of quantiles. 

     df1: vector of numerator degrees of freedom. 

     df2: vector of denominator degrees of freedom. 

      lm: vector of noncentrality parameters. 

   iprec: a parameter governing the precision of the answer; higher
          values lead to greater precision. The default is iprec=6. For
          large lm, the true answer will exceed the returned value by
          no more than 1-pnorm(iprec). 

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

     probability that a noncentral F variable with numerator degrees of
     freedom df1, denominator degrees of freedom df2 and noncentrality
     parameter lm is less than q.

_N_O_T_E:

     Let n be the length of the longest of q, df1, df2 and lm. If any
     of q, df1, df2 and lm is of length less than n, then all values
     after the first in that vector are ignored. Only the first element
     of iprec is used.

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

     Milton Abramowitz and Irene A. Stegun, Handbook of Mathematical
     Functions, p. 947, Dover, 1970.

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

     `pf', `pchisqnc'

