NAME¶
bgraph - do a set of batch graphs to a metafile
SYNOPSIS¶
bgraph [
-type .. ][
+variable value .. ][
file .. ]
DESCRIPTION¶
Bgraph reads each graph
file in sequence and converts it to a plot
suitable for use by a metafile driver program. If no files are given, the
standard input is read.
The graph type can be defined with a
-type option. Types are simply
include files which set default values for certain variables. The actual
include file name is the type concatanated with ".plt". Typical
types are "scatter", "line", and "curve". A
scatter graph shows only points. A line graph shows only lines connecting
points. A curve graph shows both points and connecting lines.
Variables can be set explicitly with
+variable value options. The
following standard graph variables are supported:
- fthick
- The frame thickness, valued from 0 to 4. A value of 0 turns
the frame off.
- grid
- The grid: 1 is on, 0 is off.
- include
- The include file name. Graph input is taken from the file.
If the file is not found in the current directory, it is searched for in a
set of standard locations.
- legend
- The legend title.
- othick
- The origin axis thickness, valued from 0 to 4. A value of 0
turns the origin off.
- period
- The period for a polar plot. For a plot in degrees, use
360. For radians, use 6.283. A value of 0 (the default) indicates a
Cartesian plot.
- subtitle
- The graph subtitle.
- symfile
- The point symbol metafile.
- tstyle
- The frame tick mark style. The default value is 1, which is
outward tick marks. A value of 2 is inward ticks, 3 is cross ticks. A
value of 0 disables frame tick marks.
- title
- The graph title.
- xlabel
- The x axis label.
- xmap
- The x axis mapping function. An x axis mapping
xmap(x)=log(x) produces a log x axis.
- xmax
- The x axis maximum.
- xmin
- The x axis minimum.
- xstep
- The x axis step.
- ylabel
- The y axis label.
- ymap
- The y axis mapping function. An y axis mapping
ymap(y)=log(y) produces a log y axis.
- ymax
- The y axis maximum.
- ymin
- The y axis minimum.
- ystep
- The y axis step.
In addition to the standard graph variables, each curve has a set of variables.
The variables for curve 'A' all begin with the letter 'A'; the variables for
curve 'B' all begin with the letter 'B', and so on. Up to 8 curves are
supported on a single graph, 'A' through 'H'. The variables for curve 'A' are:
- A
- The function for curve 'A'. If Adata is undefined,
xmin, xmax and Anpoints are used to determine which x
values to plot. If Adata is defined and A is a function of a
single variable (ie. A(x)), data values are interpreted as x values to be
plotted. If Adata is defined and A is a function of two
variables (ie. A(x,y)), data values are interpreted as (x,y) pairs and
A becomes a mapping function for the data.
- Acolor
- The color for curve A. The values 1-4 map to black, red,
green, and blue respectively. A value of 0 turns curve A off.
- Adata
- The point data for curve 'A'. If Adata is set to the
name of a file, data is read and interpreted from that file. If
Adata is set to a command (beginning with an exclamation, '!'), the
output of the command is read as data. Otherwise, data is read from the
current file. Data values are separated by white space and/or commas. A
semicolon or end of file indicates the end of data.
- Alabel
- The label for curve 'A'. The curve label is printed in the
legend when a curve is defined.
- Alintype
- The line type for curve 'A', valued from 0 to 4. A value of
0 turns line drawing off. A value of 1 is solid, 2 is dashed, 3 is dotted,
and 4 is dot-dashed.
- Anpoints
- The number of symbol points for curve 'A'. If Adata
is defined, all points will be connected with the selected curve line, but
only Anpoints points will be indicated with a symbol. This prevents
messy graphs when large number of points are defined. If A is
defined and Adata is not, Anpoints is used along with
xmin and xmax to determine which x values to plot.
- Asymsize
- The symbol radius for curve 'A'. The default size is 100. A
value of 0 turns symbols off.
- Asymtype
- This is the name of a segment in symfile which
defines the graphics symbol for curve 'A'.
- Athick
- The line thickness for curve 'A', valued from 0 to 4. A
thickness of 0 turns line drawing off.
A graph file contains definitions for graph and curve variables. These
definitions fall one per line in the following formats:
vreal = expression # real variable
vfunction(x) = expression(x) # function
vstring = "string" # string variable
vdata = filename # data file
vdata = "!command" # data generator
variable = continued \
line # newline escaped
vdata = # data
v1 v2 v3 v4 ... ;
Comments are preceded by a '#', and continue to the end of the line. Except for
comments, the newline can be escaped with a backslash. Note that in the
special case where data is contained in the graph file, a definition will
continue over more than one line. Data values can be separated by commas or
white space, and reading continues until a semicolon is reached. No comments
are allowed in the data section of a file.
An expression is an algebraic formula containing numbers, variables, functions,
and the standard operators {+,-,*,/,^,(,)} (see
icalc(1)). Besides the
variables described in the last section, definitions of intermediate real
variables and functions are allowed for convenience. They may be used in
expressions of graph and curve variables.
EXAMPLE¶
A file to graph the sine function is:
title = "Sine Function from 0 to Pi"
PI = 3.141592653589793
A(x) = sin(x)
xmin = 0
xmax = PI
Anpoints = 100
Or, to graph selected points:
title = "Sine Function at 0, .2, .6, and .8"
A(x) = sin(x)
Adata =
0 , .2
.6 , .8
;
The commands to plot these files might be:
bgraph -line sine1.plt | psmeta | lpr
bgraph -curve +ymin -1 +ymax 1 sine2.plt | x11meta
FILES¶
/usr/local/lib/meta/*.mta /usr/local/lib/meta/*.plt *.plt
AUTHOR¶
Greg Ward
BUGS¶
There is no mechanism provided for undefining a variable. An axis mapping
function which is not invertible (monotonically increasing or decreasing)
confuses the program terribly.
SEE ALSO¶
dgraph(1),
gcomp(1),
icalc(1),
igraph(1),
metafile(5),
x11meta(1)