| . \" DS - display. If .DS C, center; L, left-adjust; I, indent. |
| .de DS |
| .KS |
| .nf |
| .\\$1D \\$2 \\$1 |
| .ft 1 |
| .ps \\n(PS |
| .if \\n(VS>40 .vs \\n(VSu |
| .if \\n(VS<=39 .vs \\n(VSp |
| .. |
| .de D |
| .ID \\$1 |
| .. |
| .de CD |
| .XD |
| .ce 1000 |
| .. |
| .de ID |
| .XD |
| .if t .in +0.5i |
| .if n .in +8 |
| .if \\n(.$ .if !"\\$1"I" .if !"\\$1"" .in \\n(OIu |
| .if \\n(.$ .if !"\\$1"I" .if !"\\$1"" .in +\\$1n |
| .. |
| .de LD |
| .XD |
| .. |
| .de XD |
| .nf |
| .nr OI \\n(.i |
| .SP \\n(DVu |
| .sp \\n(DVu |
| .. |
| . \" BD - block display: save everything, then center it. |
| .de BD |
| .XD |
| .nr BD 1 |
| .nf |
| .in \\n(OIu |
| .di DD |
| .. |
| . \"DE - display end |
| .de DE |
| .ce 0 |
| .if \\n(BD>0 .DF |
| .nr BD 0 |
| .in \\n(OIu |
| .KE |
| .SP \\n(DVu |
| .sp \\n(DVu |
| .fi |
| .. |
| . \" DF - finish a block display to be recentered. |
| .de DF |
| .di |
| .if \\n(dl>\\n(BD .nr BD \\n(dl |
| .if \\n(BD<\\n(.l .in (\\n(.lu-\\n(BDu)/2u |
| .nr EI \\n(.l-\\n(.i |
| .ta \\n(EIuR |
| .nf |
| .DD |
| .in \\n(OIu |
| .. |
