ColorRamps              package:hexbin              R Documentation

_C_o_l_o_r _R_a_m_p_s _o_n _P_e_r_c_e_p_t_u_a_l_l_y _L_i_n_e_a_r _S_c_a_l_e_s

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

     Functions for returning colors on perceptually linear scales,
     where steps correspond to just detectable differences.

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

     LinGray (n, beg=1, end=92)
     BTC     (n, beg=1, end=256)
     LinOCS  (n, beg=1, end=256)
     heat.ob (n, beg=1, end=256)
     magent  (n, beg=1, end=256)
     plinrain(n, beg=1, end=256)

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

       n: number of colors to return from the ramp

     beg: begining of ramp, integer from 1-255

     end: end of ramp, integer from 1-255

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

     Several precalulated color ramps, that are on a perceptually
     linear color scale.  A perceptually linear color scale is a scale
     where each jump corresponds to a just detectable difference in
     color and the scale is percieved as linear by the human eye
     (emprically determined).

     When using the ramps, if 'beg' is less than 'end' the ramp will be
     reversed.

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

     returns an array of colors

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

     Nicholas Lewin-Koh

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

     Haim Levkowitz (1997) _Color Theory and Modeling for Computer
     Graphics, Visualization, and Multimedia Applications_. Kluwer
     Academic Publishers, Boston/London/Dordrecht. <URL:
     http://www.cs.uml.edu/~haim/ColorCenter/>

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

     'rainbow', 'terrain.colors', 'rgb', 'hsv'

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

     h <- hexbin(rnorm(10000),rnorm(10000))
     plot(h, colramp= BTY)
     ## looks better if you shave the tails:
     plot(h, colramp= function(n){LinOCS(n,beg=15,end=225)})

