r.weight2(1)		      Grass User's Manual		  r.weight2(1)



NNAAMMEE
	rr..wweeiigghhtt22  - Weighted overlay raster map layer analysis program.
       _(_G_R_A_S_S _R_a_s_t_e_r _P_r_o_g_r_a_m_)

SSYYNNOOPPSSIISS
	rr..wweeiigghhtt22 [[_o_u_t_p_u_t] [_a_c_t_i_o_n] [_c_o_l_o_r]
	rr..wweeiigghhtt22 [oouuttppuutt==_o_p_t_i_o_n] [aaccttiioonn==_o_p_t_i_o_n] [ccoolloorr==_o_p_t_i_o_n]

DDEESSCCRRIIPPTTIIOONN
	 _r_._w_e_i_g_h_t_2  is the non-interactive version of _r_._w_e_i_g_h_t.  Both programs
       allow the user to assign numeric values (i.e., "weights") to individual
       category  values within raster map layers.  These weights are then dis-
       tributed locationally throughout a raster map layer based on  the  dis-
       tribution  of  the categories with which they are associated.  The user
       can weight the categories of several raster map layers in a data  base.
       Such weighted raster map layers can then be overlain.
	_r_._w_e_i_g_h_t_2  will  combine  weights  in  the overlain map layers by cell
       location.


       A resulting output raster map layer  depicts  the  combination  of  map
       layer  weights  across a landscape.  These values represent a hierarchy
       of suitability  for  some  user-defined	purpose.   To  obtain  a  more
       detailed description, see the manual entry for _r_._w_e_i_g_h_t .
       _O_u_t_p_u_t raster map must be specified     (no default)
       _A_c_t_i_o_n must be either (_a_d_d or _m_u_l_t)     (default: add)
       _C_o_l_o_r  table  for the new raster map (grey | wave | ramp)     (default:
       grey)
	Once the  _r_._w_e_i_g_h_t_2 command line is entered, the  user	will  need  to
       enter  a  raster  map layer name and assign numeric values to its cate-
       gories.	Values can be assigned to the categories of up to  six	raster
       map  layers  within  _r_._w_e_i_g_h_t_2 in a single analysis.  Help is available
       to the user by typing  rr..wweeiigghhtt22 hheellpp.

EEXXAAMMPPLLEE
       The following is the format in which data should be entered to
	_r_._w_e_i_g_h_t_2:  Raster_layer1  [Reclass  rule  1a]	 [Reclass   rule   1b]
       Raster_layer2 [Reclass rule 2a] etc.  end

       Raster_layer:   _r_a_s_t_e_r___m_a_p  OR  "_r_a_s_t_e_r___m_a_p  _i_n	_m_a_p_s_e_t"  Reclass rule:
       (example)  1 = 5 OR 20 thru 50 = 10 (must leave spaces between the cat-
       egory, =, and value entries)


       Example: (the prompts are shown in bold) >>   r.weight2 sites add wave >>
       soils


       ssooiillss>>  1 thru 20 = 5 ssooiillss>>  21 thru 30 = 10 ssooiillss>>  landcover


       llaannddccoovveerr>>  1 = 2 llaannddccoovveerr>>  2 = 4 llaannddccoovveerr>>  3 thru 8 = 6 llaannddccoovveerr>>
       end





NNOOTTEESS
       The user must be knowledgeable about _r_._w_e_i_g_h_t
	to  run _r_._w_e_i_g_h_t_2.  _r_._w_e_i_g_h_t_2 does not provide the user with a listing
       of raster map layers or	map  layer  categories.   Users  unsure  about
       raster map layer names should run the GRASS program _g_._l_i_s_t .  To obtain
       a listing of the categories for a raster map layer run _r_._r_e_p_o_r_t .


       The user can create an input file containing the  data  needed  to  run
       _r_._w_e_i_g_h_t_2.   This file must list the raster map layer and reclass rules
       in the format shown in the above example.   The	prompts  must  not  be
       included in the file.  This file can be directed into  _r_._w_e_i_g_h_t_2 at the
       command line by typing

       rr..wweeiigghhtt22 oouuttppuutt aaccttiioonn ccoolloorr <<	iinnppuutt__ffiillee


BBUUGGSS
       When entering data for the reclass rules, if the user does not  include
       spaces between the category, =, and value, the program will assume that
       the entry is a raster map layer.

SSEEEE AALLSSOO
       _g_._l_i_s_t

       _r_._c_o_m_b_i_n_e

       _r_._i_n_f_e_r

       _r_._r_e_p_o_r_t

       _r_._w_e_i_g_h_t

AAUUTTHHOORR
       Dave Gerdes, 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.weight2(1)
