Subversion Repositories planix.SVN

.TH GRAP 1

.SH NAME

grap \- pic preprocessor for drawing graphs

.SH SYNOPSIS

.B grap

[

.I file ...

]

.SH DESCRIPTION

.I Grap

is a

.IR pic (1)

preprocessor for drawing graphs on a typesetter.

Graphs are surrounded by the

.I troff

`commands'

.B \&.G1

and

.BR  \&.G2 .

Data are scaled and plotted,

with tick marks supplied automatically.

Commands exist to modify the frame,

add labels, override the default ticks,

change the plotting style,

define coordinate ranges and transformations,

and include data from files.

In addition,

.I grap

provides the same loops, conditionals, and macro processing that

.I pic

does.

.PP

.BI frame

.B ht

.I e

.B wid

.I e

.B top

.B dotted

.IR ... :

Set the frame around the graph to specified

.B ht

and

.BR wid ;

default is 2 by 3 (inches).

The line

.I styles

.RB ( dotted ,

.BR dashed ,

.BR invis ,

.BR solid

(default))

of the 

.I sides

.RB ( top ,

.BR bot ,

.BR left ,

.BR right )

of the frame can be set

independently.

.PP

.B label

.I side

.B \&"a label"

.B \&"as a set of strings"

.IR adjust :

Place label on specified side; default side is bottom.

.I adjust

is

.B up

(or

.B down

.B left

.BR right )

.I expr

to shift default position;

.B width

.I expr

sets the width explicitly.

.PP

.BI ticks

.I side

.B in

.B at

.IR "optname expr, expr, ..." :

Put ticks on

.I side

at

.I "expr, ...,

and label with

.I \&"expr"\f1.

If any

.I expr

is followed by "...", label tick with "...",

and turn off all automatic labels.

If "..." contains

.BR %f 's,

they will be interpreted as

.B printf

formatting instructions for the tick value.

Ticks point

.B in

or

.B out

(default out).

Tick iterator: instead of

.B at

.IR \&... ,

use

.BI from

.I expr

.B to

.I expr

.B by

.I "op expr

where

.I op

is optionally

.B +-*/

for additive or multiplicative steps.

.B by

can be omitted, to give steps of size 1.

If no ticks are requested, they are supplied automatically;

suppress this with

.B ticks

.BR off .

Automatic ticks normally

leave a margin of 7% on each side; set this to anything by

.B margin

.B =

.IR expr .

.PP

.B grid

.I "side linedesc"

.B at

.IR "optname expr, expr, ..." :

Draw grids perpendicular to

.I side

in style

.I linedesc

at

.I "expr, ....\&

Iterators and labels work as with ticks.

.PP

.B coord

.I optname

.B x

.I "min, max"

.B y

.I "min, max"

.B "log x

.BR " log y" :

Set range of coords and optional log scaling on either or both.

This overrides computation of data range.

Default value of

.I optname

is current coordinate system

(each

.B coord

defines a new coordinate system).

.PP

.B plot

.I \&"str"

.B at

.IR point ;

.B

.I \&"str"

.B at

.IR point :

Put

.I str

at

.IR point .

Text position can be qualified with

.BR rjust ,

.BR ljust ,

.BR above ,

.BR below

after "...".

.PP

.B line

.B from

.I point

.B to

.IR "point linedesc" :

Draw line from here to there.

.B arrow

works in place of

.BR line .

.PP

.B next

.I optname

.B at

.IR "point linedesc" :

Continue plot of data in

.I optname to

.IR point ;

default is current.

.PP

.BI draw

.IR "optname linedesc ..." :

Set mode for

.BR next :

use this style from now on,

and plot "..." at each point (if given).

.PP

.BI new

.IR "optname linedesc ..." :

Set mode for

.BR next ,

but disconnect from previous.

.PP

A list of numbers

.I "x y1 y2 y3 ...

is treated as 

.B plot

.B bullet

.B at

.IR x,y1 ;

.B plot

.B bullet

.B at

.IR x,y2 ;

etc., or as

.B next

.B at

.I x,y1

etc., if

.B draw

is specified.

Abscissae of 1,2,3,... are provided if there is only one input number per line.

.PP

A

point

.I "optname expr, expr

maps the point to the named coordinate system.

A

.I linedesc

is one of

.B dot

.B dash

.B invis

.B solid

optionally followed by an expression.

.PP

.BI define

.I name

.BI { whatever } \f1:

Define a macro.

There are macros already defined for standard plotting

symbols like

.BR bullet ,

.BR circle ,

.BR star ,

.BR plus ,

etc., in

.BR /sys/lib/grap.defines ,

which is included if it exists.

.PP

.I var

.B =

.IR expr :

Evaluate an expression.

Operators are

.B=

.B +

.B -

.B *

and

.BR / .

Functions are

.B log

and

.B exp

(both base 10),

.BR sin ,

.BR cos ,

.BR sqrt ;

.B rand

returns random number on [0,1);

.BI max( e , e )\f1,

.BI min( e , e )\f1,

.BI int( e )\f1.

.PP

.B print

.IR expr ;

.B print

\fL"\f2...\fL"\f1:

As a debugging aid, print

.I expr

or

.I string

on the standard error.

.PP

.B copy

\fL"\fIfile name\fL"\fR:

Include this file right here.

.PP

.B copy

.B thru

.IR macro :

Pass rest of input (until

.BR \&.G2 )

through

.IR macro ,

treating each field (non-blank, or "...") as an argument.

.I macro

can be the name of a macro previously defined,

or the body of one in place, like

.BR "/plot $1 at $2,$3/" .

.PP

.B copy

.B thru

.I macro

.B until

\fL"\fIstring\fL"\fR:

Stop copy when input is

.I string

(left-justified).

.PP

.BI pic

.IR "remainder of line" :

Copy to output with leading blanks removed.

.PP

.BI graph

.IR "Name pic-position" :

Start a new frame, place it at specified position,

e.g.,

.B graph

.B Thing2

.BR "with .sw at Thing1.se + (0.1,0)" .

.I Name

must be capitalized to keep

.I pic

happy.

.PP

.BI \&. "anything at beginning of

.IR line :

Copied verbatim.

.PP

.B sh

.BI % anything

.BR % :

Pass everything between the

.BR % 's

to the shell;

as with macros,

.B %

may be any character and

.I anything

may include newlines.

.PP

.B #

.IR anything :

A comment, which is discarded.

.PP

Order is mostly irrelevant; no category is mandatory.

Any arguments on the

.B \&.G1

line are placed on the generated

.B \&.PS

line for

.IR pic .

.SH EXAMPLES

.EX

.ps -1

.vs -1

\&.G1

frame ht 1 top invis right invis

coord x 0, 10 y 1, 3 log y

ticks left in at 1 "bottommost tick", 2,3 "top tick"

ticks bot in from 0 to 10 by 2

label bot "silly graph"

label left "left side label" "here"

grid left dashed at 2.5

copy thru / circle at $1,$2 /

1 1

2 1.5

3 2

4 1.5

10 3

\&.G2

.G1

frame ht 1 top invis right invis

coord x 0, 10 y 1, 3 log y

ticks left in at 1 "bottommost tick", 2,3 "top tick"

ticks bot in from 0 to 10 by 2

label bot "silly graph"

label left "left side label" "here"

grid left dashed at 2.5

copy thru / circle at $1,$2 /

1 1

2 1.5

3 2

4 1.5

10 3

.G2

.ps

.vs

.EE

.SH FILES

.TF /sys/lib/grap.defines

.TP

.B /sys/lib/grap.defines

definitions of standard plotting characters, e.g., bullet

.SH SOURCE

.B /sys/src/cmd/grap

.SH "SEE ALSO"

.IR pic (1), 

.IR troff (1)

.br

J. L. Bentley and B. W. Kernighan,

``GRAP\(emA Language for Typesetting Graphs'',

.I

Unix Research System Programmer's Manual,

Tenth Edition, Volume 2.