Provided by: plplot-doc_5.10.0-0ubuntu5_all 
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(3plplot) if you want to shade
a number of contiguous regions using continuous colors. In particular the edge contours
are treated properly in plshades(3plplot). If you attempt to do contiguous regions with
plshade1(3plplot) (or plshade(3plplot)) the contours at the edge of the shade are
partially obliterated by subsequent plots of contiguous shaded regions. plshade1(3plplot)
differs from plshade(3plplot) by the type of the first argument. Look at the argument
list below, plcont(3plplot) 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(3plplot) is used in examples/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 (const 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 otherwise. 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.
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(3plplot) does nothing.
shade_max (PLFLT, input)
Defines the upper end of the interval to be shaded. If shade_max <= shade_min,
plshade1(3plplot) does nothing.
sh_cmap (PLINT, input)
Defines color map. If sh_cmap=0, then sh_color is interpreted as a color map 0
(integer) index. If sh_cmap=1, then sh_color is interpreted as a color map 1
floating-point index which ranges from 0. to 1.
sh_color (PLFLT, input)
Defines color map index if cmap0 or color map input value (ranging from 0. to 1.)
if cmap1.
sh_width (PLFLT, 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 (PLFLT, 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 (PLFLT, 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.
fill (void (*) (PLINT, const PLFLT *, const PLFLT *), input)
Routine used to fill the region. Use plfill(3plplot). 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 rectangular 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
rectangles. For example a plot in polar coordinates has to have rectangular 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(3plplot) for identity mapping, and pltr1(3plplot) and pltr2(3plplot)
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(3plplot),
pltr1(3plplot), or pltr2(3plplot).
pltr_data (PLPointer, input)
Extra parameter to help pass information to pltr0(3plplot), pltr1(3plplot),
pltr2(3plplot), or whatever routine that is externally supplied.
AUTHORS
Many developers (who are credited at http://plplot.sourceforge.net/credits.php) have
contributed to PLplot over its long history.
SEE ALSO
PLplot documentation at http://plplot.sourceforge.net/documentation.php.
February, 2014 PLSHADE1(3plplot)