A collection of groff,pic,and eqn macros used in many of my local files. Note that many of these are not my own work and come from a variety of sources.

y.tmac

.defcolor LOCALBLUE rgb 0.1 0.1 0.9
.de NOTE
\m[LOCALBLUE]NOTE\m[]: \\$*
..
.de PROOF
.ft BI
PROOF
.ft
..
.defcolor LOCALRED rgb 1 0.0 0.0
.de TODO
\m[LOCALRED]TODO\m[]: \\$1
..

.\" .BU [[n|N|i|I|a|A num] | symbol]

.\" Example Usage

.\" .BU
.\" first line.
.\" .BU
.\" second line
.\" .LP
.\" .BU n
.\" first line.
.\" .BU
.\" second line
.\" .LP
.\" The macro looks like 18 ,
.\" *********************

.\" ************************My BU macro**********************************
.\"
.\" Predefine some registers and strings. These are also reset with
.\" every .NH [i] invocation.
.nr bu 0
.ds symbol \\(bu
.ds numeric
.de BU \"{{{
.\"
.\" If there is an argument, its either a symbol, or a numeric format & value
.\"
.if !'\\$1'' \{\
. ds symbol
. ds numeric \$1
. ie '\\$1'n' .af bu 1
\" set format to 1 ...
. el \{\
.  ie '\\$1'N' .af bu 001
\" set format to 001 ...
.  el \{\
.  ie '\\$1'i' .af bu i
\" set format to lower case roman numerals
.  el \{\
.  ie '\\$1'I' .af bu I \" set format to upper case roman numerals
.  el \{\
.  ie '\\$1'a' .af bu a \" set format to lower case alphabetic
.  el \{\
.  ie '\\$1'A' .af bu A
\" set format to upper case alphabetic
.  el \{\
.  ds symbol \\$1
.  ds numeric
.  \}
.  \}
.  \}
.  \}
.  \}
. \}
.\"
.\" If there is a second argument, it must be the start value
.\"
. if !'\\*[numeric]'' \{\
.  ie '\\$2'' \{\
.  nr bu 1
.  \}
.  el \{\
.  nr bu \\$2
.  \}
. \}
.\}
.\"
.ie !'\\*[numeric]'' \{\
. IP \\n(bu
. af bu 1
. nr bu \\n(bu+1
. ie '\\*[numeric]'n' .af bu 1
. el \{\
.  ie '\\*[numeric]'N' .af bu 001
.  el .af bu \\*[numeric]
. \}
.\}
.el \{\
. IP \\*[symbol]
.\}
.. \"}}}
.de striketrough \"{{{
\Z'\\$1'\v'-.25m'\D'l \w'\\$1'u 0'\v'.25m'\\$2
.. \"}}}

.ig 
TODO: find link for the origin of these macros
Colored Box Backgrounds

Use .ll to set the line length so the box knows how big to be
..
.de BB \"{{{
.br
.in  1n
.ll -1n
.di BX
..
.de EB
.br
.di
.in
.ll
.nr BW \\n(dl+1n
.nr BH \\n(dn+.5v
.ne \\n(BHu+.5v
.in 0
\M[grey90]\v'-.5v'\D'P \\n(BWu 0 0 \\n(BHu -\\n(BWu 0 0 -\\n(BHu'\M[]
.sp -.5v
.nf
.BX
.in
.sp .5v
.fi
.. \"}}}

.\" EQN STUFF 
\" From manual
.EQ \" {{{
define ! 'special Ca'
define box 'special Bx'
.EN
.de Bx
.ds 0s \Z'\h'1n'\\*(0s'\
\Z'\v'\\n(0du+1n'\D'l \\n(0wu+2n 0'\D'l 0 -\\n(0hu-\\n(0du-2n'\
\D'l -\\n(0wu-2n 0'\D'l 0 \\n(0hu+\\n(0du+2n''\h'\\n(0wu+2n'
.nr 0w +2n
.nr 0d +1n
.nr 0h +1n
.nr 0skern 0
.nr 0skew 0
..
.de Ca \"{{{
.  ds 0s \
\Z'\\*(0s'\
\v'\\n(0du'\
\D'l \\n(0wu -\\n(0hu-\\n(0du'\
\v'\\n(0hu'
.. \"}}}

.\" The following is a short eqn/troff macro for creating doing
.\" several things, but mainly to create oblique (or Italics) Greek
.\" lower-case letters for mathemtical equations.
.\" Simply include this file in your initial eqn set-up:
.\" .EQ
.\" include "alphas"
.\" gsize 12
.\" delim ``
.\" .EN
.\" Note: some non-ASCII characters may differ on your set-up.
.\" Edit to taste.
.\"
.\" Written by Robert Marks, [email protected].  Vers. 1.0, Aug 22, 1995.
.\"
.EQ \" {{{ 
define Fourier '"\s+4\f[ZCMI]F\fP\s0"'
define Laplace '"\s+4\f[ZCMI]L\fP\s0"'
define lcb	% ^ roman "{"^ %
define rcb	% ^ roman "}"^ %
define Fraction	% {up 20 size -4 $1 down 25 "" back 12 size +1 "\S'+15'/\S'0'" up 5  "" fwd 6 size -4 $2} %
define Calcat % "\b'\(br\(br'" sub roman down 100 {~ $1 } %
define lower	% sub up 30 fwd 50 %
define upper	% sup up 30 %
define Integral	% {size +2 int lower $1 upper $2} %
define alpha	% "\S'+15'\s-1\H'+1'\(*a\H'0'\s+1\S'0'\h'0.2n'" %
define ALPHAit	% "\S'+15'\s-1\H'+1'\(*A\H'0'\s+1\S'0'\h'0.1n'" %
define beta	% "\S'+15'\s-1\H'+1'\(*b\H'0'\s+1\S'0'\h'0.2n'" %
define BETAit	% "\S'+15'\s-1\H'+1'\(*B\H'0'\s+1\S'0'\h'0.2n'" %
define gamma	% "\S'+15'\s-1\H'+1'\(*g\H'0'\s+1\S'0'\h'0.4n'" %
define GAMMAit	% "\S'+15'\s-1\H'+1'\(*G\H'0'\s+1\S'0'\h'0.35n'" %
define delta	% "\S'+15'\s-1\H'+1'\(*d\H'0'\s+1\S'0'\h'0.3n'" %
define DELTAit	% "\S'+15'\s-1\H'+1'\(*D\H'0'\s+1\S'0'\h'0.1n'" %
define epsilon	% "\S'+15'\s-1\H'+1'\(*e\H'0'\s+1\S'0'\h'0.2n'" %
define EPSILONit	% "\S'+15'\s-1\H'+1'\(*E\H'0'\s+1\S'0'\h'0.25n'" %
define zeta	% "\S'+15'\s-1\H'+1'\(*z\H'0'\s+1\S'0'\h'0.3n'" %
define ZETAit	% "\S'+15'\s-1\H'+1'\(*Z\H'0'\s+1\S'0'\h'0.33n'" %
define eta	% "\S'+15'\s-1\H'+1'\(*y\H'0'\s+1\S'0'\h'0.17n'" %
define ETAit	% "\S'+15'\s-1\H'+1'\(*Y\H'0'\s+1\S'0'\h'0.28n'" %
define theta	% "\S'+15'\s-1\H'+1'\(*h\H'0'\s+1\S'0'\h'0.2n'" %
define THETAit	% "\S'+15'\s-1\H'+1'\(*H\H'0'\s+1\S'0'\h'0.2n'" %
define iota	% "\S'+15'\s-1\H'+1'\(*i\H'0'\s+1\S'0'\h'0.17n'" %
define IOTAit	% "\S'+15'\s-1\H'+1'\(*I\H'0'\s+1\S'0'\h'0.33n'" %
define kappa	% "\S'+15'\s-1\H'+1'\(*k\H'0'\s+1\S'0'\h'0.3n'" %
define KAPPAit	% "\S'+15'\s-1\H'+1'\(*K\H'0'\s+1\S'0'\h'0.33n'" %
define lambda	% "\S'+15'\s-1\H'+1'\(*l\H'0'\s+1\S'0'\h'0.2n'" %
define LAMBDAit	% "\S'+15'\s-1\H'+1'\(*L\H'0'\s+1\S'0'\h'0.1n'" %
define mu	% "\S'+15'\s-1\H'+1'\(*m\H'0'\s+1\S'0'\h'0.2n'" %
define MUit	% "\S'+15'\s-1\H'+1'\(*M\H'0'\s+1\S'0'\h'0.33n'" %
define nu	% "\S'+15'\s-1\H'+1'\(*n\H'0'\s+1\S'0'\h'0.25n'" %
define NUit	% "\S'+15'\s-1\H'+1'\(*N\H'0'\s+1\S'0'\h'0.33n'" %
define xi	% "\S'+15'\s-1\H'+1'\(*c\H'0'\s+1\S'0'\h'0.2n'" %
define XIit	% "\S'+15'\s-1\H'+1'\(*C\H'0'\s+1\S'0'\h'0.25n'" %
define omicron	% "\S'+15'\s-1\H'+1'\(*o\H'0'\s+1\S'0'\h'0.2n'" %
define OMICRONit	% "\S'+15'\s-1\H'+1'\(*O\H'0'\s+1\S'0'\h'0.2n'" %
define pi	% "\S'+15'\s-1\H'+1'\(*p\H'0'\s+1\S'0'\h'0.25n'" %
define PIit	% "\S'+15'\s-1\H'+1'\(*P\H'0'\s+1\S'0'\h'0.33n'" %
define rho	% "\S'+15'\s-1\H'+1'\(*r\H'0'\s+1\S'0'\h'0.2n'" %
define RHOit	% "\S'+15'\s-1\H'+1'\(*R\H'0'\s+1\S'0'\h'0.25n'" %
define sigma	% "\S'+15'\s-1\H'+1'\(*s\H'0'\s+1\S'0'\h'0.3n'" %
define SIGMAit	% "\S'+15'\s-1\H'+1'\(*S\H'0'\s+1\S'0'\h'0.3n'" %
define tau	% "\S'+15'\s-1\H'+1'\(*t\H'0'\s+1\S'0'\h'0.3n'" %
define TAUit	% "\S'+15'\s-1\H'+1'\(*T\H'0'\s+1\S'0'\h'0.3n'" %
define upsilon	% "\S'+15'\s-1\H'+1'\(*u\H'0'\s+1\S'0'\h'0.2n'" %
define UPSILONit	% "\S'+15'\s-1\H'+1'\(*U\H'0'\s+1\S'0'\h'0.4n'" %
define phi	% "\S'+15'\s-1\H'+1'\(*f\H'0'\s+1\S'0'\h'0.2n'" %
define PHIit	% "\S'+15'\s-1\H'+1'\(*F\H'0'\s+1\S'0'\h'0.2n'" %
define psi	% "\S'+15'\s-1\H'+1'\(*q\H'0'\s+1\S'0'\h'0.35n'" %
define PSIit	% "\S'+15'\s-1\H'+1'\(*Q\H'0'\s+1\S'0'\h'0.35n'" %
define chi	% "\S'+15'\s-1\H'+1'\(*x\H'0'\s+1\S'0'\h'0.25n'" %
define CHIit	% "\S'+15'\s-1\H'+1'\(*X\H'0'\s+1\S'0'\h'0.33n'" %
define omega	% "\S'+15'\s-1\H'+1'\(*w\H'0'\s+1\S'0'\h'0.2n'" %
define OMEGAit	% "\S'+15'\s-1\H'+1'\(*W\H'0'\s+1\S'0'\h'0.2n'" %
define aleph	% "\S'+15'\s-1\H'+1'\(al\H'0'\s+1\S'0'\h'0.2n'" %
define ln	% "\S'-15'\f2ln\fP\S'0'" %
define lscr	% "\S'-15'\f2l\fP\S'0'" %
define becaus	% "\u\s+5.\s0\d\s+5.\s0\u\s+5.\s0\d" %
define times	% \(mu %
define (( "left ("
define )) "right )"
define [[ "left ["
define ]] "right ]"
define '' 'left ""'
define lt	% roman "\^<\^" %
define <	% roman "\^<\^" %
define gt	% roman "\^>\^" %
define >	% roman "\^>\^" %
define |	% roman "\^|\^" %
define /	% roman "\^\S'+18'\(br\S'0'\^"^ ^ %
define ++++	% \(pl %
define ====	% \(eq %
define prime	% \(mt %
define there4	% \(tf %
define thf	% \(tf %
define forall	% \(fa %
define oppA	% \(fa %
define exist	% \(te %
define oppE	% \(te %
define intersection	% "\(ca" %
define union	% "\(cu" %
define Exp	% roman "Exp" %
define cov	% roman "cov" %
define Cov	% roman "Cov" %
define var	% roman "var" %
define Var	% roman "Var" %
define Prob	% roman "Prob" %
define all	% ~ roman "all" ~ %
define and	% ~ roman "and" ~ %
define where	% ~ roman "where" ~ %
define subject 	% ~ roman "subject" ~ %
define st	% roman "st" %
define nd	% roman "nd" %
define rd	% roman "rd" %
define th	% roman "th" %
define n.s.	% roman "n.s." %
define s.t.	% roman "s.t." %
define tr	% roman "tr" %
define sgn	% roman "sgn" %
define RR	% "\fHI\h'-.85n'R\fP" %
define sroot    % down 20 sqrt up 20 %
define app=     % "\(mi" up 20 back 55 "\(ap" down 20 "\&" %
define -wig     % "\(mi" up 20 back 55 "\(ap" down 20 "\&" %
define wig      % "\(ap" %
define divby	% ^ "\(di" ^ %
define member	% "\(mo" %
define $	% "$" %
.EN \" }}}

.\" PIC STUFF
.PS \" {{{
# e.g. dime( 1 , 2 , DIM1 )
# dime( ht , wid , NAME, "text" )
define dime {

  $3: [
    W: line up $1/2 right $2/2
    N: line down $1/2 right $2/2
    E: line down $1/2 left $2/2
    S: line up $1/2 left $2/2
    NW: W.c
    NE: N.c
    SE: E.c
    SW: S.c
  ]
  "$4" at $3
  move to $3.s
}
define vec {
	"$1" at ($2 + ($4/2)),($3 + ($5/2))
	arrow from $2,$3 to ($2+$4),($3+$5)
}
define dvec {
	"$1" at ($2 + ($4/2)),($3 + ($5/2))
	arrow dashed from $2,$3 to ($2+$4),($3+$5)
}
# venn Diagrams
# e.g. vennDiagram1(2, 3, "1.", "A")
# move down from last box.s
# vennDiagram2(2, 3, "2.", "A", "B")
# move down from last box.s
define vennDiagram1 {
    box height $1 width $2
    $3 at last box.nw - (0.1, 0.0)
    "U" at last box.ne - (0.1, 0.1)
    circle radius last box.height/4 at last box.c
    $4 at last circle.nw + (-0.1, 0.1)
    move to last box.e
}
define vennDiagram2 {
    box height $1 width $2
    $3 at last box.nw - (0.1, 0.0)
    "U" at last box.ne - (0.1, 0.1)
    circle radius last box.height/4 at last box.c - (last box.height/8, 0)
    $4 at last circle.nw + (-0.1, 0.1)
    circle radius last box.height/4 at last box.c + (last box.height/8, 0)
    $5 at last circle.ne + (0.1, 0.1)
    move to last box.e
}
define vennDiagram3 {
    box height $1 width $2
    $3 at last box.nw - (0.1, 0.0)
    "U" at last box.ne - (0.1, 0.1)
    circle radius last box.height/4 at last box.c - (last box.height/7,
-last box.height/10)
    $4 at last circle.nw + (-0.1, 0.1)
    circle radius last box.height/4 at last box.c + (last box.height/7,
last box.height/10)
    $5 at last circle.ne + (0.1, 0.1)
    circle radius last box.height/4 at last box.c - (0, last box.height/7)
    $6 at last circle.sw - (0.1, 0.1)
    move to last box.e
}
.PE \" }}}

.de @FE
.ie !\\n[fn*open] .@error FE without FS
.el \{\
.	nr fn*open 0
.	br
.	nr par*box-fnspace +\\n[.d]
.	ev
.	fn*end-div
.\}
..
.\" --------------------------------------------------------------------
.\" B1 [fill_color [frame_color [frame_thickness]]]
.\"     start boxed text
.\"
.de B1 \"{{{
.ie \\n[.$]>0 \{\
. nr par*box-compat 0
. ds par*box-color \\$1
. ds par*box-fcolor \\*[par*box-color]
. nr par*box-fthickness 0
.
. if \\n[.$]>1 .ds par*box-fcolor \\$2
. if \\n[.$]>2 .nr par*box-fthickness \\$3
.\}
.el .nr par*box-compat 1
.
.nr par*box-fnspace 0
.br
.HTML-IMAGE
.di par*box-div			\" beginn diverting text to par*box-div
.nr \\n[.ev]:li +1n
.nr \\n[.ev]:ri +1n
.nr par*box-in \\n[.in]
.\" remember what 1n is, just in case the point size changes
.nr par*box-n 1n
.in +1n
.ll -1n
.lt -1n
.ti \\n[par*box-in]u+1n
..
.de @div-end!par*box-div
.B2
.. \"}}}
.\" end boxed text
.\" Postpone the drawing of the box until we're in the top-level diversion,
.\" in case there's a footnote inside the box.
.de B2 \"{{{
.ie '\\n(.z'par*box-div' \{\
.	br
.	if \n[.V]>.25m .sp
.	di			\" end diverting text
.	if \n[.V]>.25m .sp
.	ds@need \\n[dn]
.	par*box-mark-top
.
.	nr \\n[.ev]:ri -\\n[par*box-n]
.	nr \\n[.ev]:li -\\n[par*box-n]
.	in -\\n[par*box-n]u
.	ll +\\n[par*box-n]u
.	lt +\\n[par*box-n]u
.\"     box color isn't transparent, it must be drawn before writing the text
.	par*box-draw \\n[.i]u \\n[.l]u-(\\n[.H]u==1n*1n)
.	ev nf
.	par*box-div
.	ev
.\}
.el .@error B2 without B1
.HTML-IMAGE-END
..
.de par*box-mark-top
.ie '\\n[.z]'' \{\
.	rs
.	mk par*box-top
.\}
.el \!.par*box-mark-top
..
.de par*box-draw
.ie '\\n[.z]'' \{\
.	nr par*box-in \\n[.i]
.	nr par*box-ll \\n[.l]
.	nr par*box-vpt \\n[.vpt]
.	nr par*box-ad \\n[.j]
.	ad l            \" adjust to left
.	vpt 0           \" disable vertical position trap
.	in \\$1
.	ll \\$2
.\" we are at the top left corner
.\" calculate the opposite
.nr par*box-top \\n[par*box-top]u+\\n[dn]-\\n[par*box-fnspace]
.if \\n[par*box-fnspace]>0 .nr par*box-top -\\n[fn*need]u
.ie \\n[par*box-compat] \{\
\v'-1v+.25m'\
\D'l (u;\\n[.l]-\\n[.i]) 0'\
\D'l 0 |\\n[par*box-top]u'\
\D'l -(u;\\n[.l]-\\n[.i]) 0'\
\D'l 0 -|\\n[par*box-top]u'
.\}
.el \{\
.
.\" first draw a solid polygon(\D'P...'), after that the borders (\D'p...') 
\v'-1v+.25m'\M[\\*[par*box-color]]\D'P\
    (u;\\n[.l]-\\n[.i]) 0 \
    0 |\\n[par*box-top]u \
    -(u;\\n[.l]-\\n[.i]) 0 \
    0 -|\\n[par*box-top]u'\M[]\
\m[\\*[par*box-fcolor]]\
\D't \\n[par*box-fthickness]'\h'-\\n[par*box-fthickness]u'\D'p\
    (u;\\n[.l]-\\n[.i]) 0 \
    0 |\\n[par*box-top]u \
    -(u;\\n[.l]-\\n[.i]) 0 \
    0 -|\\n[par*box-top]u'\m[]\D't 0'
.\}
.
.	br
.	sp -1
.	in \\n[par*box-in]u
.	ll \\n[par*box-ll]u
.	vpt \\n[par*box-vpt]
.	ad \\n[par*box-ad]
.\}
.el \!.par*box-draw \\$1 \\$2
..
.\"}}} /box

\" Markdown esque syntax
.de #
.SH 1
.UL "\\$*"
.LP
..
.de ##
.SH 2
\\$*
.LP
..
.de ###
.SH 3
\\$*
.LP
..
.de ####
.SH 4
\\$*
.LP
..

.de -
.IP \(bu 2
\\$*
..

.de --
.RS
.IP \(bu 2
\\$*
.RE
..

.de Q
.KS
\m[blue]Question:\m[] \\$*
..
.de A
\m[green]Answer:\m[] \\$*
.KE
..