r.describe(1)		      Grass User's Manual		 r.describe(1)



NNAAMMEE
       rr..ddeessccrriibbee   -  Prints  terse list of category values found in a raster
       map layer.
       _(_G_R_A_S_S _R_a_s_t_e_r _P_r_o_g_r_a_m_)

SSYYNNOOPPSSIISS
       rr..ddeessccrriibbee
       rr..ddeessccrriibbee hheellpp
       rr..ddeessccrriibbee [--11rrqqdd] mmaapp==_n_a_m_e[nnvv==_s_t_r_i_n_g][nnsstteeppss==_v_a_l_u_e]

DDEESSCCRRIIPPTTIIOONN
       _r_._d_e_s_c_r_i_b_e prints a terse listing of category values found in  a  user-
       specified raster map layer.

OOPPTTIIOONNSS
       The  program  will  be run non-interactively, if the user specifies the
       name of a raster map layer and any desired flags on the	command  line,
       using the form rr..ddeessccrriibbee [--11rrqqdd] mmaapp==_n_a_m_e

       where  the  map _n_a_m_e is the name of a raster map layer whose categories
       are to be described, and the (optional) flags --11, --rr, --qq, and  --dd  have
       the meanings described below.


       Alternately,  the  user can simply type rr..ddeessccrriibbee on the command line,
       without program arguments.  In this case, the user will be prompted for
       needed  flag  settings and the parameter value using the standard GRASS
       _p_a_r_s_e_r.

   PPRROOGGRRAAMM UUSSEE
       The user can select one	of  the  following  two  output  reports  from
       _r_._d_e_s_c_r_i_b_e:

       (1) RANGE.
	      A range of category values found in the raster map layer will be
	      printed.	The range is divided  into  three  groups:   negative,
	      positive,  and  zero.  If negative values occur, the minimum and
	      maximum negative values will be  printed.   If  positive	values
	      occur,  the minimum and maximum positive values will be printed.
	      If zero occurs, this will be indicated.

       (2) FULL LIST.
	      A list of all category values that were found in the raster  map
	      layer will be printed.


       The following sample output from _r_._d_e_s_c_r_i_b_e: 0 2-4 10-13

       means  that  category  data  values  0,	2 through 4, and 10 through 13
       occurred in the named map layer.

       The user must choose to read the map layer in one of two ways:

       (1) DIRECTLY.
	      The current geographic region and mask are ignored and the  full
	      raster  map  layer  is  read.  This method is useful if the user
	      intends to _r_e_c_l_a_s_s_i_f_y or _r_e_s_c_a_l_e the data, since these functions
	      (_r_._r_e_c_l_a_s_s  and  _r_._r_e_s_c_a_l_e)  also  ignore the current _g_e_o_g_r_a_p_h_i_c
	      _r_e_g_i_o_n and _m_a_s_k.

       (2) REGIONED and MASKED.
	      The map layer is read  within  the  current  geographic  region,
	      masked by the current mask.


   NNOONN--IINNTTEERRAACCTTIIVVEE PPRROOGGRRAAMM UUSSEE
       _r_._d_e_s_c_r_i_b_e  examines a user-chosen raster map layer.  If run non-inter-
       actively, the layer name must be supplied on the command line.


       A compact list of category values that were found  in  the  data  layer
       will be printed.


       Following is a sample output: 0 2-4 10-13


   FFllaaggss::
       --ll     Print  the  output  one  value  per line, instead of the default
	      short form.  In the above example, the --11 option would output:

	      0
	      2
	      3
	      4
	      10
	      11
	      12
	      13


       --rr     Only print the range of the data.  The highest and lowest  posi-
	      tive  values,  and  the  highest and lowest negative values, are
	      output. In the above example, the --rr option would output: 0 2 13



       If  the	--11 option is also specified, the output appears with one cate-
       gory value per line.

       --qq     Quiet. The --qq option will tell r.describe  to  be  silent  while
	      reading  the raster file.  If not specified, program percentage-
	      completed messages are printed.

       --dd     Use  the	current   geographic   region	settings.    Normally,
	      _r_._d_e_s_c_r_i_b_e  will read the data layer directly, ignoring both the
	      current  region  settings  and  mask.   The  --dd	option	 tells
	      _r_._d_e_s_c_r_i_b_e to read the map layer in the current region masked by
	      the current mask (if any).


   PPaarraammeetteerrss::
       mmaapp==_n_a_m_e
	      Name of raster map.

       nnvv==_s_t_r_i_n_g
	      String representing no data cell value.

       nnsstteeppss==_v_a_l_u_e
	      Number of quantization steps.


NNOOTTEESS
       The range report will generally run faster than the full list.

SSEEEE AALLSSOO
       _p_a_r_s_e_r

AAUUTTHHOORR
       Michael Shapiro, U.S. Army Construction Engineering Research Laboratory

       _L_a_s_t _c_h_a_n_g_e_d_: _$_D_a_t_e_: _2_0_0_2_/_0_1_/_2_5 _0_5_:_4_5_:_3_4 _$



GRASS 5.0							 r.describe(1)
