r.rescale.inf(1)       Grass User's Manual	 r.rescale.inf(1)



NNAAMMEE
       rr..rreessccaallee..iinnff   - Generate a raster map layer in which the
       categories represent values in  a  database  column  which
       have been divided into equal interval units.
       _(_G_R_A_S_S_-_R_D_B_M_S _R_a_s_t_e_r _I_n_t_e_r_f_a_c_e _P_r_o_g_r_a_m_)

SSYYNNOOPPSSIISS
       rr..rreessccaallee..iinnff
       rr..rreessccaallee..iinnff hheellpp
       rr..rreessccaallee..iinnff   ttaabb==_n_a_m_e   kkeeyy==_n_a_m_e   ccooll==_n_a_m_e	ccaattss==_n_a_m_e
       iinnppuutt==_n_a_m_e oouuttppuutt==_n_a_m_e [[jjooiinn==_t_a_b_,_t_a_b_k_e_y_,_p_k_e_y_]

DDEESSCCRRIIPPTTIIOONN
       r.rescale.inf creates a	reclassed  raster  map	layer  by
       dividing  the  values in a numeric column in the currently
       selected database into equal interval units. The number of
       resulting  categories  is  determined  by the user via the
       command line parameter  [cats=].  r.rescale.inf	evaluates
       the  range  of  values for the database column and subsets
       these  values  into  equal  interval  groups  of   records
       returned by the query. For example, if the database column
       contains values which range from  1-1000  and  the  [cats]
       value  is  equal to 10 the resulting raster map layer will
       contain the 10 categories:1=1-100, 2=101-200 etc. In other
       words, each category in the new raster map layer will rep-
       resent a range of 100 values from the database column used
       in the rescale operation. The database column being evalu-
       ated must be numeric in type. To identify the  data  types
       of  columns  in a database table use the g.column.inf com-
       mand with the [-v] flag. r.rescale.inf does not take  out-
       lying data values into account. Therefore, if the range of
       values for a database column contains a limited number  of
       extreme	values	the  resulting	rescale operation will be
       skewed in the direction of these values.





CCOOMMMMAANNDD LLIINNEE OOPPTTIIOONNSS
       Parameters

       ttaabb==database_table_name
	      Table containing a column linked to category values
	      in an existing raster map.

       kkeeyy==database_column_name
	      Column  corresponding  to  category  values  in  an
	      existing raster map.

       ccooll==database_column_name
	      Column  to  base	rescale  operation  on	which  is
	      numeric in type.

       ccaattss==value
	      Number  of  categories  to  define in the resulting
	      reclass map.

       iinnppuutt==map
	      Name of an existing raster file with category  val-
	      ues  linked  to  a column in the currently selected
	      databae.

       oouuttppuutt==map
	      Name of new raster map.

       jjooiinn==tab,tabkey,pkey


       Tab is the table used to develop the  current  SQL  query.
       Tabkey  is  the database column used to relate information
       in this table with data in the table linked to  the  GRASS
       category  file. Pkey is the associated column in the table
       linked to the GRASS category  file  which  is  related  to
       tabkey in the current table.


       For  instance, assume that stf1_main is a table containing
       column values associated with category  values  in  a  the
       GRASS  raster  file  blkgrp.ids.  In addition, assume that
       stf1_main is a table containing attribute data on  age  in
       the  column pop100. In this example stf1_main is the table
       associated with the GRASS raster map and tract_blck is the
       column  linking	stf1_main to the GRASS category file. The
       column pop100 in stf1_main  will  be  the  basis  for  the
       rescale	effort.   To  specify  the rescale: rr..rreessccaallee..iinnff
       ttaabb==_s_t_f_1___m_a_i_n kkeeyy==_t_r_a_c_t___b_l_c_k ccooll==_p_o_p_1_0_0 ccaattss==_5  iinnppuutt==_b_l_k_-
       _g_r_p_._i_d_s oouuttppuutt==_p_o_p_1_0_0_._r_e_s_c_a_l_e

       Specifying  these  conditions  would  insure that all rows
       from table stf1_main  which  satisfy  the  query  criteria
       would be related to the spatial features in the GRASS data
       layer via the GRASS category values.





BBUUGGSS
       None known.



NNOOTTEE
       This program requires the Informix database software.



SSEEEE AALLSSOO
       g.column.inf,  g.select.inf,   g.stats.inf,   g.table.inf,
       d.rast.inf,    d.site.inf,    d.vect.inf,    d.what.r.inf,
       d.what.s.inf, d.what.v.inf, r.reclass.inf, v.reclass.inf



AAUUTTHHOORR
       James A. Farley, Wang Song and W. Fredrick Limp University
       of Arkansas, CAST

       _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.rescale.inf(1)
