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 oouutt--
       ppuutt==_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 val-
       ues  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 exam-
       ple, 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 represent a range of 100 val-
       ues from the database column used in the rescale operation.  The  data-
       base  column  being  evaluated must be numeric in type. To identify the
       data types of columns in a database table use the g.column.inf  command
       with  the  [-v]	flag. r.rescale.inf does not take outlying data values
       into account. Therefore, if the range of values for a  database	column
       contains a limited number of extreme values the resulting rescale oper-
       ation 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 exist-
	      ing 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 values 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 link-
       ing 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 spa-
       tial 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)
