autoKey              package:ifultools              R Documentation

_A_u_t_o_m_a_t_i_c _k_e_y _p_l_a_c_e_m_e_n_t

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

     Automatically places a key in the sparsest location of the space
     spanned by the the x and y input coordinates.

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

     autoKey(x, y=NULL, args.=NULL, nquadrant=5)

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

       x: if 'y' is not 'NULL', this argument is a numeric vector
          containing the abscissa (x-axis) values for the current plot.
          If 'y=NULL', this argument is taken as a numeric vector of
          ordinate (y-axis) values.

   args.: a list of arguments that define the legend ala the 'key'
          function. Default: 'NULL' (no matpoints).

nquadrant: an integer denoting the number of quadrants to partition the
          space spanned by x and y. For example, if 'nquadrants=3', the
          x-y space is partitioned into a 3x3 grid of equisized blocks.
          Default: 5.

       y: a numeric vector containing the ordinate (y-axis) values in
          the current plot. If 'NULL', the 'x' input argument is taken
          as the y-axis values while the x-axis values are extracted
          from 'x' via the 'positions' function. If there are no
          positions available, then the sequence '1:length(x)' is used
          as the x-axis positions. Default: 'NULL'.

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

     The argument 'args.' is a list of arguments that define the key
     and 'nquadrant' is the number of equi-sized quadrants to use in
     dividing the space in both the x- and y-direction. e.g., if
     nquadrant=3, the x-y plane is partitioned into a 3x3 uniform grid
     and the position of the sparsest quadrant (as defined by
     'sparsetQuadrant') is used to place the key. This function does
     not take into consideration lines connecting the data points and
     only considers the spatial distribution of the points in the x-y
     plane. Futhermore, this function assumes that 'par("usr")' is
     approximately 'c(range(x),range(y))', i.e., that the user will not
     explicitly make space outside span of the data to place the key.
     In this case, the user should explicitly place the key as usual.

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

     no output is returned.

_N_o_t_e:

     The key as described by 'args.' is positioned in estimated
     sparsest region of the specified data set.

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

     'autoText', 'sparsestQuadrant', 'mergeList'.

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

     zkey <- list(x=-1,y=-1,
     lines=list(type=c("o","l"), pch=c(18,0), lty=1, col=1:2),
     border=1,
     corner=c(1,1),
     cex=1.5 )

     old.mfrow <- par(mfrow=c(2,2))

     ## rectangular hole in cloud 
     set.seed(100)
     N <- 10024
     y <- rnorm(N)
     x <- seq(N)
     xhole <- x > .4*N & x < .9*N
     yhole <- y > -2 & y < 2
     hole  <- xhole & yhole
     y <- y[!hole]
     x <- x[!hole]
     plot(x, y, type="p")
     autoKey(x, y, args=zkey)

     ## linear chirp (more room on left) 
     y <- sin(.125*pi*100*((0:99)/100)^2)
     plot(y, type="p")
     autoKey(y, args=zkey)

     ## quadratic 
     x <- seq(-5,5)
     y <- x^2
     plot(x,y,type="p")
     autoKey(x, y, args=zkey)

     ## circle 
     tt <- seq(0,2*pi,length=100)
     x  <- sin(tt)
     y  <- cos(tt)
     plot(x, y, type="p")
     autoKey(x, y, args=zkey)
     par(old.mfrow)

