d.histogram(1)	       Grass User's Manual	   d.histogram(1)



NNAAMMEE
       dd..hhiissttooggrraamm   -	Displays a histogram in the form of a pie
       or bar chart for a user-specified raster file.
       _(_G_R_A_S_S _D_i_s_p_l_a_y _P_r_o_g_r_a_m_)

SSYYNNOOPPSSIISS
       dd..hhiissttooggrraamm
       dd..hhiissttooggrraamm hheellpp
       dd..hhiissttooggrraamm  [--qqnnCC]  mmaapp==_n_a_m_e  [ccoolloorr==_n_a_m_e]   [ssttyyllee==_n_a_m_e]
       [nnsstteeppss==_v_a_l_u_e]

DDEESSCCRRIIPPTTIIOONN
       _d_._h_i_s_t_o_g_r_a_m displays the category-value distribution for a
       user-specified raster map layer, in  the  form  of  a  bar
       chart  or  a  pie chart.  The display will be displayed in
       the active display frame on the	graphics  monitor,  using
       the  colors  in	the  raster map layer's color table.  The
       program determines the raster file's category  value  dis-
       tribution by counting cells.

OOPPTTIIOONNSS
       The  user can run this program either non-interactively or
       interactively.  The program will be run	non-interactively
       if  the	user specifies the name of a raster map layer and
       (optionally) any other desired parameters and flags on the
       command line, using the form: dd..hhiissttooggrraamm [--zzqqnnCC] mmaapp==_n_a_m_e
       [ccoolloorr==_n_a_m_e] [ssttyyllee==_n_a_m_e] [nnsstteeppss==_v_a_l_u_e]

       If a map name is given on  the  command	line,  any  other
       parameter values left unspecified on the command line will
       be set to their default values (see below).   Alternately,
       the  user can simply type dd..hhiissttooggrraamm on the command line,
       without program arguments. In this case, the user will  be
       prompted  for  needed  inputs and option choices using the
       standard GRASS _p_a_r_s_e_r interface.



   FFllaaggss::
       --qq     Gather the histogram quietly, without printing mes-
	      sages on program progress to the user's terminal.

       --nn     Display information for null cells.

       --CC     Report  for  ranges  defined  in cats file (fp maps
	      only).




   PPaarraammeetteerrss::
       mmaapp==_n_a_m_e
	      The name of an existing raster  map  layer  in  the
	      user's  current mapset search path for which a his-
	      togram is to be displayed.

       ccoolloorr==_n_a_m_e
	      The name of the color to	be  used  for  the  axis,
	      text-labels, and tic-marks on the pie or bar chart.
	      Options: _w_h_i_t_e, _r_e_d, _o_r_a_n_g_e, _y_e_l_l_o_w,  _g_r_e_e_n,  _b_l_u_e,
	      _i_n_d_i_g_o, _m_a_g_e_n_t_a, _v_i_o_l_e_t, _b_r_o_w_n, _g_r_a_y, and _b_l_a_c_k
	      Default: _w_h_i_t_e

       ssttyyllee==_n_a_m_e
	      The  style  of  the  histogram.  If ssttyyllee==_b_a_r, then
	      _d_._h_i_s_t_o_g_r_a_m will displays  the  statistics  in  the
	      form of a bar chart. If ssttyyllee==_p_i_e, then _d_._h_i_s_t_o_g_r_a_m
	      will display the statistics in the form  of  a  pie
	      chart.
	      Options: _b_a_r or _p_i_e
	      Default: _b_a_r

       nnsstteeppss==_v_a_l_u_e
	      Number  of  steps to divide the data range into (FP
	      maps only).
	      Default: _2_5_5


NNOOTTEESS
       _d_._h_i_s_t_o_g_r_a_m uses the current  geographic  region  settings
       and the current mask (if one exists).


       _d_._h_i_s_t_o_g_r_a_m  uses  the  colors  in the map's color look-up
       table (i.e., the  map's	_c_o_l_r  or  _c_o_l_r_2  file).  To  view
       results	correctly  on  the display monitor, make sure the
       color mode is correctly	set  before  running  _d_._h_i_s_t_o_g_r_a_m
       (i.e., execute dd..ccoolloorrmmooddee mmooddee==ffllooaatt).


       _d_._h_i_s_t_o_g_r_a_m  does  not  erase the active frame before dis-
       playing output.

SSEEEE AALLSSOO
       _d_._c_o_l_o_r_m_o_d_e  _d_._c_o_l_o_r_s   _d_._c_o_l_o_r_t_a_b_l_e   _d_._d_i_s_p_l_a_y   _d_._e_r_a_s_e
       _g_._r_e_g_i_o_n _r_._m_a_s_k _r_._s_t_a_t_s _p_a_r_s_e_r

AAUUTTHHOORR
       Dave Johnson

	DBA Systems, Inc.

	10560 Arrowhead Drive

	Fairfax, Virginia 22030

       _L_a_s_t _c_h_a_n_g_e_d_: _$_D_a_t_e_: _2_0_0_2_/_0_1_/_2_5 _0_5_:_4_5_:_3_2 _$



GRASS 5.0					   d.histogram(1)
