plotellipse              package:StatDA              R Documentation

_P_l_o_t _E_l_l_i_p_s_e

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

     Plots an ellipse with percentage tolerance and a certain location
     and covariance.

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

     plotellipse(x.loc, x.cov, perc = 0.98, col = NULL, lty = NULL)

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

   x.loc: the location vector 

   x.cov: the covariance 

    perc: defines the percentage and should be a (vector of) number(s)
          between 0 and 1 

col, lty: graphical parameters 

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

     First the radius of the covariance is calculated and then the
     ellipses for the provided  percentages are plotted at the certain
     location.

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

     Plot with ellipse.

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

     Peter Filzmoser <P.Filzmoser@tuwien.ac.at>

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

     C. Reimann, P. Filzmoser, R.G. Garrett, and R. Dutter: Statistical
     Data Analysis Explained. Applied Environmental Statistics with R.
     John Wiley and Sons Inc. To appear.

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

     data(moss)
     Ba=log10(moss[,"Ba"])
     Ca=log10(moss[,"Ca"])
     plot.new()
     plot.window(xlim=range(Ba),ylim=c(min(Ca)-1,max(Ca)))

     x=cbind(Ba,Ca)
     plotellipse(apply(x,2,mean),cov(x),perc=c(0.5,0.75,0.9,0.98))

