Graphics Directives and Options
When you set up a graphics object in
Mathematica, you typically give a list of graphical elements. You can include in that list
graphics directives which specify how subsequent elements in the list should be rendered.
In general, the graphical elements in a particular graphics object can be given in a collection of nested lists. When you insert graphics directives in this kind of structure, the rule is that a particular graphics directive affects all subsequent elements of the list it is in, together with all elements of sublists that may occur. The graphics directive does not, however, have any effect outside the list it is in.
Only the rectangle in the first sublist is affected by the GrayLevel directive.
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GrayLevel[i]  gray level between 0 (black) and 1 (white) 
RGBColor[r,g,b]  color with specified red, green and blue components, each between 0 and 1 
Hue[h]  color with hue h between 0 and 1 
Hue[h,s,b]  color with specified hue, saturation and brightness, each between 0 and 1 
Basic Mathematica color specifications.
Mathematica accepts the names of many colors directly as color specifications. These color names, such as
Red,
Gray,
LightGreen and
Purple, are implemented as variables which evaluate to an
RGBColor specification. The color names can be used interchangeably with color directives.
The first plot is colored with a color name, while the second one has a finetuned RGBColor specification.
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The function
Hue[h] provides a convenient way to specify a range of colors using just one parameter. As
h varies from 0 to 1,
Hue[h] runs through red, yellow, green, cyan, blue, magenta, and back to red again.
Hue[h, s, b] allows you to specify not only the "hue", but also the "saturation" and "brightness" of a color. Taking the saturation to be equal to one gives the deepest colors; decreasing the saturation toward zero leads to progressively more "washed out" colors.
When you give a graphics directive such as
RGBColor, it affects
all subsequent graphical elements that appear in a particular list.
Mathematica also supports various graphics directives which affect only specific types of graphical elements.
The graphics directive
PointSize[d] specifies that all
Point elements which appear in a graphics object should be drawn as circles with diameter
d. In
PointSize, the diameter
d is measured as a fraction of the width of your whole plot.
Mathematica also provides the graphics directive
AbsolutePointSize[d], which allows you to specify the "absolute" diameter of points, measured in fixed units. The units are
of an inch, approximately printer's points.
PointSize[d]  give all points a diameter d as a fraction of the width of the whole plot 
AbsolutePointSize[d]  give all points a diameter d measured in absolute units 
Graphics directives for points.
This makes each point have a diameter equal to onetenth of the width of the plot.
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Here each point has size 3 in absolute units.
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Thickness[w]  give all lines a thickness w as a fraction of the width of the whole plot 
AbsoluteThickness[w]  give all lines a thickness w measured in absolute units 
Dashing[{w_{1},w_{2},...}]  show all lines as a sequence of dashed segments, with lengths w_{1}, w_{2}, ... 
AbsoluteDashing[{w_{1},w_{2},...}]  use absolute units to measure dashed segments 
Graphics directives for lines.
This generates a list of lines with different absolute thicknesses.
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Here is a picture of the lines.
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The
Dashing graphics directive allows you to create lines with various kinds of dashing. The basic idea is to break lines into segments which are alternately drawn and omitted. By changing the lengths of the segments, you can get different line styles.
Dashing allows you to specify a sequence of segment lengths. This sequence is repeated as many times as necessary in drawing the whole line.
This gives a dashed line with a succession of equallength segments.
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Dashing can be turned off by specifying an empty list. Here, Dashing is turned off for only the second line.
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Graphics directives which require a numerical size specification can also accept values of
Tiny,
Small,
Medium, and
Large. For each directive, these values have been finetuned to produce an appearance which will seem appropriate to the human eye.
This specifies a large thickness with medium dashing.
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This specifies that the entire multipoint should use large, green points.
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One way to use
Mathematica graphics directives is to insert them directly into the lists of graphics primitives used by graphics objects. Sometimes, however, you want the graphics directives to be applied more globally, and for example to determine the overall "style" with which a particular type of graphical element should be rendered. There are typically graphics options which can be set to specify such styles in terms of lists of graphics directives.
PlotStyle>style  specify a style to be used for all curves in Plot 
PlotStyle>{{style_{1}},{style_{2}},...}  specify styles to be used (cyclically) for a sequence of curves in Plot 
MeshStyle>style  specify a style to be used for a mesh in density and surface graphics 
BoxStyle>style  specify a style to be used for the bounding box in threedimensional graphics 
Some graphics options for specifying styles.
This generates a plot in which all curves are specified to use the same style.
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A different PlotStyle expression can be used to give specific styles to each curve.
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The various "style options" allow you to specify how particular graphical elements in a plot should be rendered.
Mathematica also provides options that affect the rendering of the whole plot.
Background>color  specify the background color for a plot 
BaseStyle>color  specify the base style for a plot, affecting elements not affected by PlotStyle 
Prolog>g  give graphics to render before a plot is started 
Epilog>g  give graphics to render after a plot is finished 
Graphics options that affect whole plots.
This draws the plot in white on a gray background.
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This makes the axes white as well.
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