


PLSHADE1(3)                 PLplot API                PLSHADE1(3)


NAME
       plshade1 - Shade individual region on the basis of value

SYNOPSIS
       plshade1(a,  nx,  ny,  defined,  xmin,  xmax,  ymin,  ymax,  shade_min,
       shade_max,   sh_cmap,   sh_color,   sh_width,   min_color,   min_width,
       max_color, max_width, fill, rectangular, pltr, pltr_data)

DESCRIPTION
       Shade  individual region on the basis of value.  Use plshades(3) if you
       want to shade a number of contiguous regions using  continuous  colors.
       In particular the edge contours are treated properly in plshades(3). If
       you attempt to do contiguous regions with plshade1(3)  (or  plshade(3))
       the contours at the edge of the shade are partially obliterated by sub-
       sequent plots of contiguous shaded regions.  plshade1(3)  differs  from
       plshade(3)  by  the  type  of the first argument.  Look at the argument
       list below, plcont(3) and the PLplot documentation for more information
       about the transformation from grid to world coordinates.  Shading NEEDS
       DOCUMENTATION, but as a stopgap look at how plshade(3) is used in exam-
       ples/c/x15c.c

       Redacted  form:   General: plshade1(a, defined, xmin, xmax, ymin, ymax,
       shade_min,   shade_max,   sh_cmap,   sh_color,   sh_width,   min_color,
       min_width,  max_color,  max_width,  fill, rectangular, pltr, pltr_data)
       Perl/PDL: plshade1(a, xmin, xmax,  ymin,  ymax,  shade_min,  shade_max,
       sh_cmap,   sh_color,   sh_width,   min_color,   min_width,   max_color,
       max_width, fill, rectangular, defined, pltr, pltr_data)


       This function is used in example 15.

ARGUMENTS
       a (PLFLT *, input)
              Contains array to be plotted. The array must have been  declared
              as PLFLT a[nx][ny].

       nx (PLINT, input)
              First dimension of array "a".

       ny (PLINT, input)
              Second dimension of array "a".

       defined (PLINT (*) (PLFLT, PLFLT), input)
              User function specifying regions excluded from the shading plot.
              This function accepts x and y coordinates as input arguments and
              must return 0 if the point is in the excluded region or 1 other-
              wise. This argument can be NULL if all the values are valid.

       xmin (PLFLT, input)
              Defines the "grid" coordinates.  The data a[0][0] has a position
              of  (xmin,ymin), a[nx-1][0] has a position at (xmax,ymin) and so
              on.





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PLSHADE1(3)                 PLplot API                PLSHADE1(3)


       xmax (PLFLT, input)
              Defines the "grid" coordinates.  The data a[0][0] has a position
              of  (xmin,ymin), a[nx-1][0] has a position at (xmax,ymin) and so
              on.

       ymin (PLFLT, input)
              Defines the "grid" coordinates.  The data a[0][0] has a position
              of  (xmin,ymin), a[nx-1][0] has a position at (xmax,ymin) and so
              on.

       ymax (PLFLT, input)
              Defines the "grid" coordinates.  The data a[0][0] has a position
              of  (xmin,ymin), a[nx-1][0] has a position at (xmax,ymin) and so
              on.

       shade_min (PLFLT, input)
              Defines the lower end of the interval to be shaded. If shade_max
              <= shade_min, plshade1(3) does nothing.

       shade_max (PLFLT, input)
              Defines the upper end of the interval to be shaded. If shade_max
              <= shade_min, plshade1(3) does nothing.

       sh_cmap (PLINT, input)
              Defines color map.

       sh_color (PLFLT, input)
              Defines color map index if cmap0 or color map input value (rang-
              ing from 0. to 1.) if cmap1.

       sh_width (PLINT, input)
              Defines width used by the fill pattern.

       min_color (PLINT, input)
              Defines  pen color, width used by the boundary of shaded region.
              The min values are used for the shade_min boundary, and the  max
              values  are used on the shade_max boundary.  Set color and width
              to zero for no plotted boundaries.

       min_width (PLINT, input)
              Defines pen color, width used by the boundary of shaded  region.
              The  min values are used for the shade_min boundary, and the max
              values are used on the shade_max boundary.  Set color and  width
              to zero for no plotted boundaries.

       max_color (PLINT, input)
              Defines  pen color, width used by the boundary of shaded region.
              The min values are used for the shade_min boundary, and the  max
              values  are used on the shade_max boundary.  Set color and width
              to zero for no plotted boundaries.

       max_width (PLINT, input)
              Defines pen color, width used by the boundary of shaded  region.
              The  min values are used for the shade_min boundary, and the max



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PLSHADE1(3)                 PLplot API                PLSHADE1(3)


              values are used on the shade_max boundary.  Set color and  width
              to zero for no plotted boundaries.

       fill (void (*) (PLINT, PLFLT *, PLFLT *), input)
              Routine used to fill the region.  Use plfill(3).  Future version
              of plplot may have other fill routines.

       rectangular (PLBOOL, input)
              Set rectangular to true if rectangles map  to  rectangles  after
              coordinate  transformation with pltrl.  Otherwise, set rectangu-
              lar to false. If rectangular is set to true,  plshade  tries  to
              save  time by filling large rectangles.  This optimization fails
              if the coordinate transformation distorts the shape  of  rectan-
              gles.  For example a plot in polar coordinates has to have rect-
              angular set to false.

       pltr (void (*) (PLFLT, PLFLT, PLFLT *, PLFLT *, PLPointer) , input)
              Pointer to function that defines transformation between  indices
              in  array  z and the world coordinates (C only).  Transformation
              functions are provided in the PLplot library: pltr0(3) for iden-
              tity  mapping,  and pltr1(3) and pltr2(3) for arbitrary mappings
              respectively defined by one-  and  two-dimensional  arrays.   In
              addition,  user-supplied  routines for the transformation can be
              used as well.  Examples of all of these approaches are given  in
              the  PLplot  documentation.  The  transformation function should
              have the form given by any of pltr0(3), pltr1(3), or pltr2(3).

       pltr_data (PLPointer, input)
              Extra parameter to help pass information to pltr0(3),  pltr1(3),
              pltr2(3), or whatever routine that is externally supplied.


AUTHORS
       Geoffrey  Furnish  and  Maurice LeBrun wrote and maintain PLplot.  This
       man page was automatically generated from the  DocBook  source  of  the
       PLplot   documentation,   maintained   by  Alan  W.  Irwin  and  Rafael
       Laboissiere.

SEE ALSO
       PLplot documentation at http://plplot.sourceforge.net/resources.

















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