Syntax: DENSITY { x y } v { p1 p2 }
Qualifiers: \POLAR, \LEGEND, \PARTIAL, \DERIV, \PROFILES, \XPROFILE,
\YPROFILE, \BORDER, \HISTOGRAM, \RESET, \AXES, \LOG
Defaults: if v is a matrix: x = [1;2;3;...], y = [1;2;3;...],
p1 = 0, p2 = 1, \NOPOLAR, \BORDER, \AXES, \NOLEGEND,
\NOPROFILE, \RESET, \-LOG
Solid filled regions in colour is the default density type. No
qualifiers are needed to produce this type of drawing. The range
of values of the matrix is divided into eight equal levels, and a
different colour is associated with each level. By default, a value
is interpolated at each pixel location within the matrix region so
as to give smoothly joined regions.
Additional Information on:
Syntax: DENSITY\RANDOM { x y } v { p1 p2 }
Qualifiers: \POLAR, \PARTIAL, \DERIV, \COLOUR, \PROFILES,
\XPROFILE, \YPROFILE, \BORDER, \RESET, \AXES
Defaults: if v is a matrix: x = [1;2;3;...], y = [1;2;3;...],
\NOPOLAR, \BORDER, \AXES, \NOPROFILE, \RESET, \NOCOLOUR,
p1 = 0, p2 = 1
A value is interpolated at every pixel location within the region. That
value is normalized to lie between 0 and 1 and then compared to a randomly
generated number. A point is drawn if the square of the normalized value
is greater than the random number.
Additional Information on:
Syntax: DENSITY\DIFFUSION { x y } v { p1 p2 }
Qualifiers: \POLAR, \PARTIAL, \DERIV, \PROFILES, \XPROFILE,
\YPROFILE, \BORDER, \RESET, \AXES
Defaults: if v is a matrix: x = [1;2;3;...], y = [1;2;3;...],
\NOPOLAR, \BORDER, \AXES, \NOPROFILE, \RESET,
p1 = 0, p2 = 1
Diffusion is a form of digital halftoning. A threshold is fixed at
0.5, where the values are interpolated at each pixel location and
normalized to be between 0 (white) and 1 (black). The resulting
binary output value of 0 or 1 is compared with the original gray level
value. The difference is called the error for that location. The signal
consisting of past error values is passed through an error filter to
produce a correction value to be added to future input values. Errors
are thus diffused over a weighted neighborhood.
Additional Information on:
Syntax: DENSITY\POINTS { x y } v { p1 p2 }
DENSITY\POINTS\DITHER d { x y } v { p1 p2 }
DENSITY\POINTS\LEVELS lvl { x y } v { p1 p2 }
DENSITY\POINTS\LEVELS\DITHER d lvl { x y } v { p1 p2 }
Qualifiers: \POLAR, \LEGEND, \PARTIAL, \DERIV, \PROFILES, \XPROFILE,
\YPROFILE, \BORDER, \RESET, \DITHER, \CONTOURS, \AREAS,
\VOLUMES, \AXES, \LINES, \LEVELS, \EQUALLY_SPACED, \LOG
Defaults: if v is a matrix: x = [1;2;3;...], y = [1;2;3;...],
d = [ 1;1; 2;1; 2;2; 3;2; 3;3; 4;3; 4;4; 5;5; 6;6; 0;0 ],
\NOPOLAR, \BORDER, \AXES, \NOLEGEND, \NOPROFILE, \RESET,
\-LOG, p1 = 0, p2 = 1, ten equally spaced contour levels
By default, the range of values is divided into 10 equal levels and a
different dithering pattern is associated with each level. The interpolated
value at every pixel location within the data region is calculated to
determine the level for that point. The dithering pattern for that level
determines whether that pixel is to be lit up.
Additional Information on:
Syntax: DENSITY\BOXES { x y } v { p1 p2 { q1 q2 { r }}}
Qualifiers: \POLAR, \PARTIAL, \DERIV, \PROFILES, \XPROFILE,
\YPROFILE, \BORDER, \RESET, \AXES
Defaults: if v is a matrix: x = [1;2;3;...], y = [1;2;3;...],
p1 = 0, p2 = 1, q1 = 0, q2 = 1, r = 1
\NOPOLAR, \BORDER, \AXES, \NOPROFILE, \RESET,
A box is drawn, centred at location (x,y), with relative size
determined by v. The optional parameter r is a scale value which
controls the size of the boxes. For each box, the width and height
is multiplied by r. The default value of r is 1.
Additional Information on:
By default, axes are drawn for the density plot. If the density plot is to be overlayed on an existing set of axes, use the \NOAXES qualifier and no axes will be drawn. The axis scales will be left at their current values.
The \BORDER qualifier is valid only if v is a matrix. By default, the boundary of the matrix is outlined within the axes. If this boundary is not desired, use the \NOBORDER qualifier.
By default, the entire range of possible density levels will be used to determine the minimum and maximum density levels. If the \PARTIAL qualifier is used, the minimum and maximum density levels will be determined by the region contained within the axes. To zoom in on a particular region for more detail, pre-set the axis scales using the SCALES command.
If the \DERIV qualifier is used, the derivative of the data is used for plotting instead of the raw data itself.
The qualifiers \PROFILES, \XPROFILE and \YPROFILE are valid only if v is a matrix.
Additional Information on:
By default, the vectors x and y are assumed to represent rectangular coordinates. If the \POLAR qualifier is used, x and y are assumed to represent polar coordinates, with x the radial component and y the angular component, in degrees. The values are converted to rectangular coordinates, but the vectors are returned unchanged.