CHARACTERS

CHARACTERS

Plot Control Command

Specifies character types (A, B, ..., Z, 1, 2, 3, ..., circle, square, triangle, diamond, star, etc.) to appear at the plot points of each trace on subsequent plots.

CHARACTERS <type 1> <type 2> <type 3> etc.
where <type> specifies the desired character symbol. Up to 100 character symbols can be listed.

Enter HELP CHARACTER TYPES for a list of available plot symbols.

CHARACTER SAVE

This syntax saves the current settings of the CHARACTER command.

CHARACTER RESTORE

This syntax restores the settings of the CHARACTER command saved by a prior CHARACTER SAVE command.

CHARACTERS X BLANK STAR
CHARACTERS A B C D E
CHARACTERS STAR CIRCLE SQUARE DIAMOND
CHARACTERS STAR ALL
CHARACTERS ALL STAR
CHARACTERS

Characters are specified by trace. All characters belonging to the same trace are plotted with the same plot symbol.

The BAR, SPIKE, CHARACTER, and LINE switch all work independently of each other. That is, a plot point can be a line, a character, a spike or a bar or any combination of the above.

There are approximately 10 commands for controlling the attributes of the plotted character. See the RELATED COMMANDS section below.

User's sometimes wish to draw a plot symbol at every N points on a trace. This is handled in DATAPLOT through the creation of a tag variable. For example, to plot every fifth point do something like the following:
LET NINC = 5
LET N = SIZE Y
LET TAG = SEQUENCE 1 1 N
LET TAG = MOD(TAG,NINC)
LET TAG = -1 SUBSET TAG <> 1
LINE BLANK SOLID
CHARACTER CIRCLE BLANK
PLOT Y X SUBSET TAG = 1 AND
PLOT Y X


More complex patterns are also possible (all values with the same value for the tag variable are plotted with the same character attributes).

The CHARACTER <SAVE/RESTORE> was motivated for use by the Tcl/Tk graphical interface. However, it can also be used directly by the user. A typical use would be to save the current settings before a command, such as the box plot, that requires special settings for the CHARACTER command. The settings could then be easily restored after the special plot.

This feature was implemented 1998/5.

The CHARACTERS command with no arguments sets the character type to blank for all traces. The CHARACTERS command with the word ALL before or after the specified type assigns that character type to all traces; thus CHARACTER X ALL or CHARACTER ALL X assigns the character X to all traces.

The following special settings for CHARACTER were implemented 2000/1.

ROWID	-	uses the row number as the plot character
ROWLABEL	-	uses the row label as the plot character
XVALUE	-	uses the x-coordinate of the point as the plot character
YVALUE	-	uses the y-coordinate of the point as the plot character
XYVALUE	-	uses (x-coor,y-coor) as the plot character
TVALUE	-	uses the tag value as the plot character (Dataplot assigns a curve-id, the tag, to each point)
ZVALUE	-	this is a special form that is specific to certain commands. For a few commands (currently the DEX CONTOUR PLOT and the CROSS TABULATE PLOT, but we expect a few additional plots to support this form in future releases), Dataplot writes a numeric value into an internal array. The value in this array is used as the plot symbol. Using this with unsupported plot types may have unpredictable results (it will depend on what is stored in the internal array). This option is typically set automatically by Dataplot in the background, so currently users should not set this directly.

The ROWID and ROWLABEL are typically only used for the PLOT command (i.e., not for HISTOGRAM, etc.). This option keeps track of any subsetting (i.e., SUBSET/FOR/EXCEPT clauses on the plot command) when identifying the point. However, the results may be unpredictable for graphics other than the PLOT command.

The most common use of this command is to identify specific points on the plot (typically with the ROWLABEL option). A typical sequence would be

CHARACTER X
PLOT Y X
PRE-ERASE OFF
LIMITS FREEZE
CHARACTER ROWLABEL
PLOT Y X SUBSET Y > 90

The following special forms of the command can be used to set the character settings for specific graph types
CHARACTER BOX PLOT
CHARACTER TUFTE BOX PLOT
CHARACTER VIOLIN PLOT
CHARACTER I PLOT
CHARACTER CONTROL CHART
CHARACTER ERROR BAR PLOT

Dataplot currently allows for 100 settings of the CHARACTER command. There are situations where more than 100 traces are used on a plot. For example, with the syntax
PLOT Y X X

the number of traces for the plot will equal the number of unique values for X.

When the number of traces exceeds 100, Dataplot will repeat the character settings. That is, trace 101 will use setting 1, trace 102 will use setting 2, and so on.

There may be cases where you want to reserve the first few settings and start the repeat for later settings. You can use the command

SET CHARACTER REPEAT OFFSET <value>

to specify an offset for the repeat. For example, if you enter

SET CHARACTER REPEAT OFFSET 2

then trace 101 will use character setting 3, traces 102 will use character setting 4, and so on.

An example of this would be

CHARACTER X ALL
CHARACTER BLANK
LINE BLANK ALL
LINE SOLID
.
SET CHARACTER REPEAT OFFSET 1
PLOT Y2 X2 AND
PLOT Y X X


Here character setting 1 is reserved for the plot of Y2 versus X2 and the character settings for PLOT Y X X will all be set to X.

All characters are blank.

None

PLOT	=	Generates a data or function plot.
CHARACTERS	=	Sets the types for plot characters.
CHARACTER ANGLE	=	Sets the angle for plotting characters with the text command.
CHARACTER AUTOMATIC	=	Specifies a variable to be used as the arguments to the CHARACTER command.
CHARACTER CASE	=	Sets the cases for plot characters.
CHARACTERS COLORS	=	Sets the colors for plot characters.
CHARACTER FILL	=	Sets the fill switches for plot characters.
CHARACTER FONT	=	Sets the fonts for plot characters.
CHARACTER HW	=	Sets the heights and widths for plot characters.
CHARACTER JUSTIFICATION	=	Sets the justifications for plot characters.
CHARACTER OFFSET	=	Sets the offsets for plot characters.
CHARACTERS SIZES	=	Sets the sizes for plot characters.
CHARACTER THICKNESS	=	Sets the thicknesses for plot characters.
CHARACTER WIDTH	=	Sets the widths for plot characters.
LINES	=	Sets the types for plot lines.
SPIKE	=	Sets the on/off switches for plot spikes.
BAR	=	Sets the on/off switches for plot bars.

Presentation Graphics

Pre-1987
1988/11: CHARACTER ERROR BAR PLOT
1998/02: CHARACTER
2000/01: CHARACTER ROWID, CHARACTER ROWLABEL
2000/01: CHARACTER XVALUE, CHARACTER YVALUE, CHARACTER XYVALUE
2000/01: CHARACTER TVALUE, CHARACTER ZVALUE
2003/02: CHARACTER VIOLIN PLOT
2010/06: Allow 16 characters for CHARACTER settings

 
. POLLUTION SOURCE ANALYSIS, LLOYD CURRIE, DATE--1990
. SUBSET OF CURRIE.DAT REFERENCE FILE
.
LET ID2 = DATA 1 1 1 1 1 2 2 2 2 2 2 2 2 2 2 2 2
SERIAL READ LEAD
164 426 59 98 312 263 607 497 213 54 160 262 547 325 419 94 70
END OF DATA
SERIAL READ POT
106 175 61 79 94 121 424 328 107 218 140 179 246 231 245 339 99
END OF DATA
.
CHARACTER X1 X2 Y1 Y2
LINE BLANK ALL
LEGEND 1 X - POTASSIUM
LEGEND 2 Y - LEAD
.
TITLE DEMONSTRATE CHARACTER COMMAND
LET X = SEQUENCE 1 1 17
PLOT POT X ID2 AND
PLOT LEAD X ID2