prerex(5)

1PREREX(5)                                                            PREREX(5)
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NAME

6       prerex_format -- a format for prerequisite-chart descriptions
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DESCRIPTION

9       This  manual  describes  the  format of prerequisite-chart descriptions
10       that can be processed by [pdf]latex (normally  using  a  suitable  pre‐
11       rex.sty(7)  style file) and edited using the prerex(1) interactive edi‐
12       tor (or by any conventional text editor).
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TERMINOLOGY

15       A prerequisite chart consists of a number of course  boxes,  linked  by
16       arrows.   Courses  are  either  half  or  full,  and may be required or
17       optional (or neither).  Each course  box  can  contain  a  course  code
18       (upper  left corner), a course title (lower half), and timetable infor‐
19       mation (upper right corner).  An arrow can  be  either  a  prerequisite
20       (solid),  a corequisite (dotted), or recommended (dashed).  When a con‐
21       ventional arrow would be inappropriate, a mini course just above a tar‐
22       get box can be used.
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STRUCTURE

25       The file should contain exactly one instance of a LaTeX environment
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27       \begin{chart} instruction ... \end{chart}
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29       with  at  most  one  instruction per line.  Note that a program such as
30       prerex(1) analyzes prerex-format files without using TeX; for  example,
31       macro definitions will be ignored and macro calls will not be expanded.
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33       Instructions  may  be preceded by white space.  Lines that start with %
34       are treated as comments and ignored.  The order of instructions is  not
35       significant except that the instruction for the source and target box o
36       an arrow should precede the instruction for the arrow.  The instruction
37       formats are described in the following sections.
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COURSE BOXES

40       The instructions producing course boxes have the following forms:
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42       \halfcourse x,y:{code}{title}{timetable}
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44       \fullcourse x,y:{code}{title}{timetable}
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46       \reqhalfcourse x,y:{code}{title}{timetable}
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48       \reqfullcourse x,y:{code}{title}{timetable}
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50       \opthalfcourse x,y:{code}{title}{timetable}
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52       \optfullcourse x,y:{code}{title}{timetable}
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54       where  x,y  are the coordinates of the centerpoint of the box, relative
55       to the origin of the coordinate system at the lower-left corner of  the
56       diagram.  The code, title, and timetable arguments are arbitrary (well-
57       bracketed) text, possibly with LaTeX markup.
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59       The following are similar but take an additional  argument  to  specify
60       the (non-default) background color of the course box:
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62              \halfcoursec x,y:{code}{title}{timetable}{color}
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64              \fullcoursec x,y:{code}{title}{timetable}{color}
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66              \reqhalfcoursec x,y:{code}{title}{timetable}{color}
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68              \reqfullcoursec x,y:{code}{title}{timetable}{color}
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70              \opthalfcoursec x,y:{code}{title}{timetable}{color}
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72              \optfullcoursec x,y:{code}{title}{timetable}{color}
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MINI COURSE BOXES AND TEXT

75       A mini course is produced by an instruction of the form
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77       \mini x,y:{code}
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79       A text line is inserted into the chart by an instruction of the form
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81       \text x,y:{line-of-text}
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83       The  maximum  allowed  length  of a course-code may be smaller that the
84              maximum allowed for a line of text.
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ARROWS

87       Arrows between course boxes (or from a mini to a course box)  are  pro‐
88       duced by instructions of the form
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90       \prereq x0,y0,x1,y1:
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92       \coreq x0,y0,x1,y1:
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94       \recomm x0,y0,x1,y1:
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96       These  produce, respectively, solid, dotted, and dashed arrows from the
97       course box (or mini) centered at coordinates x0,y0 to  the  course  box
98       centered at coordinates x1,y1.
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100       In some implementations, certain arrows by default have a non-zero cur‐
101       vature.  It is possible to override the default curvature for a partic‐
102       ular arrow by using the instructions
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104       \prereqc x0,y0,x1,y1;c:
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106       \coreqc x0,y0,x1,y1;c:
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108       \recommc x0,y0,x1,y1;c:
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110       where c is an integer in the range -100:100 specifying the desired cur‐
111       vature; for example, c=0 will produce a straight arrow. To  change  the
112       default  curvature, the user program may redefine the \DefaultCurvature
113       command.
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COORDINATE GRID

116       The following instruction produces a coordinate grid, which  is  useful
117       for editing a diagram:
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119       \grid
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121       This  is normally placed before all the other instructions so that grid
122       lines are in the  background,  covered  by  course  boxes,  minis,  and
123       arrows.
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WEB LINKS

126       Course  boxes may be linked to web addresses.  The URL for course boxes
127       may be set by the user  by  redefining  the  \CourseURL  command;  when
128       called for a course box, it is supplied with three arguments, the x and
129       y coordinates of the box, mini, or textline, and the code  argument  of
130       the course box. For example,
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132       \renewcommand{\CourseURL}[3]{http://www.cs.queensu.ca/undergradu‐
133              ate/courses/#3.html}
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135       is appropriate for courses at the School of Computing, Queen's  Univer‐
136       sity.   The  first two arguments can be used to display the coordinates
137       of a box, mini, or textline in some PDF viewers while the mouse  hovers
138       over it when the source file is being edited.
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AUTHOR

141       R. D. Tennent (rdt@cs.queensu.ca)
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