B_PLOT Name
B_PLOT
Purpose
This procedure contours a data by drawing each element of an
array as a rectangular box.
Category
Graphics Calling Sequence
B_PLOT,data,x,y
Inputs
data: A two dimensional array of values to be plotted
x: A vector specifying the X coordinates for the plotted data
y: A vector specifying the Y coordinates for the plotted data
Keyword Parameters
BLANK_VALUE:
A value which if encountered in the mask
prevents data being drawn in the corresponding
box. The default value is 1.
C_COLOURS:
A vector of colour indexes to use when drawing
the boxes.
CEIL:
Indicates the use of the CEIL function when
interpolating the mask. Requires the INTERP_FACTOR
keyword.
FLOOR:
Indicates the use of the FLOOR function when
interpolating the mask. Requires the INTERP_FACTOR
keyword.
INTERP_FACTOR:
The number of gridpoints+1 which should be
added between the points specified by x and
y. Only integers are allowed. Both x and y
are interpolated identically.
C_LEVELS:
A vector containing the levels to use when binning
the data. If there are more levels than colours
specified the colours are used in cyclic fashion
as necessary.
LRG_VAL:
A large value that sets the lower limit on masked data
MASK:
A 2-dimensional integer array containing a mask to be
used when drawing the data. When BLANK_VALUE is
encountered in mask the corresponding grid box is not
coloured.
N_COLOURS:
The number of colours to use when drawing the
data. This is superceded by specifying the
levels. The default is to use 100 colours from
colour index 3 to 103.
NOERASE:
Don't draw axes or create a new data scaling. Just
draw the boxes.
OUTLINE:
This a diagnostic option. Each coloured box will
be outlined with a border. Boxes are not all the
same size as a run length encoding scheme is used
to draw them.
ROUND:
Indicates the use of the ROUND function when
interpolating the mask. Requires the INTERP_FACTOR
keyword. This is the default.
SML_VAL:
A small (or negative) value that sets the upper limit on
masked data.
_EXTRA: This procedure takes extra keywords. Examples are
values such as TITLE, [XY]TITLE, [XY]RANGE, etc.
Uses
box.pro
Restrictions
None that I know of. Comments
This routine makes use of a run-length encoding scheme to
reduce the size of postscript output.
Example
B_PLOT,RandomU(s,100,100),FIndGen(100),FIndGen(100)
Modification History
Written by: Edward C. Wiebe, 2000-07-14.
Modified: Edward C. Wiebe, 2002-03-07 (added the
c_levels keyword)
Modified: Edward C. Wiebe, 2002-11-01 (added a new RLE
scheme)
Modified: Daithi Stone (stoned@csag.uct.ac.za), 2009-12-08 (added
box.pro to dependency list)