4.3.3 Document control registers

The following is a list of document control number registers. For the sake of consistency, set registers related to margins at the beginning of your document, or just after the RP macro. You can set other registers later in your document, but you should keep them together at the beginning to make them easy to find and edit as necessary.

Margin Settings

Register: \n[PO]

Defines the page offset (i.e., the left margin). There is no explicit right margin setting; the combination of the PO and LL registers implicitly define the right margin width.

Effective: next page.

Default value: 1i.

Register: \n[LL]

Defines the line length (i.e., the width of the body text).

Effective: next paragraph.

Default: 6i.

Register: \n[LT]

Defines the title length (i.e., the header and footer width). This is usually the same as LL, but not necessarily.

Effective: next paragraph.

Default: 6i.

Register: \n[HM]

Defines the header margin height at the top of the page.

Effective: next page.

Default: 1i.

Register: \n[FM]

Defines the footer margin height at the bottom of the page.

Effective: next page.

Default: 1i.

Text Settings

Register: \n[PS]

Defines the point size of the body text. If the value is larger than or equal to 1000, divide it by 1000 to get a fractional point size. For example, ‘.nr PS 10250’ sets the document’s point size to 10.25p.

Effective: next paragraph.

Default: 10p.

Register: \n[VS]

Defines the space between lines (line height plus leading). If the value is larger than or equal to 1000, divide it by 1000 to get a fractional point size. Due to backwards compatibility, VS must be smaller than 40000 (this is 40.0p).

Effective: next paragraph.

Default: 12p.

Register: \n[PSINCR]

Defines an increment in point size, which is applied to section headings at nesting levels below the value specified in GROWPS. The value of PSINCR should be specified in points, with the p scaling factor, and may include a fractional component; for example, ‘.nr PSINCR 1.5p’ sets a point size increment of 1.5p.

Effective: next section heading.

Default: 1p.

Register: \n[GROWPS]

Defines the heading level below which the point size increment set by PSINCR becomes effective. Section headings at and above the level specified by GROWPS are printed at the point size set by PS; for each level below the value of GROWPS, the point size is increased in steps equal to the value of PSINCR. Setting GROWPS to any value less than 2 disables the incremental heading size feature.

Effective: next section heading.

Default: 0.

Register: \n[HY]

Defines the hyphenation level. HY sets safely the value of the low-level hy register. Setting the value of HY to 0 is equivalent to using the nh request.

Effective: next paragraph.

Default: 14.

Register: \n[FAM]

Defines the font family used to typeset the document.

Effective: next paragraph.

Default: as defined in the output device.

Paragraph Settings

Register: \n[PI]

Defines the initial indentation of a (PP macro) paragraph.

Effective: next paragraph.

Default: 5n.

Register: \n[PD]

Defines the space between paragraphs.

Effective: next paragraph.

Default: 0.3v.

Register: \n[QI]

Defines the indentation on both sides of a quoted (QP macro) paragraph.

Effective: next paragraph.

Default: 5n.

Register: \n[PORPHANS]

Defines the minimum number of initial lines of any paragraph that should be kept together, to avoid orphan lines at the bottom of a page. If a new paragraph is started close to the bottom of a page, and there is insufficient space to accommodate PORPHANS lines before an automatic page break, then the page break is forced, before the start of the paragraph.

Effective: next paragraph.

Default: 1.

Register: \n[HORPHANS]

Defines the minimum number of lines of the following paragraph that should be kept together with any section heading introduced by the NH or SH macros. If a section heading is placed close to the bottom of a page, and there is insufficient space to accommodate both the heading and at least HORPHANS lines of the following paragraph, before an automatic page break, then the page break is forced before the heading.

Effective: next paragraph.

Default: 1.

Footnote Settings

Register: \n[FL]

Defines the length of a footnote.

Effective: next footnote.

Default: \n[LL] * 5 / 6.

Register: \n[FI]

Defines the footnote indentation.

Effective: next footnote.

Default: 2n.

Register: \n[FF]

The footnote format:

0

Print the footnote number as a superscript; indent the footnote (default).

1

Print the number followed by a period (like 1.) and indent the footnote.

2

Like 1, without an indentation.

3

Like 1, but print the footnote number as a hanging paragraph.

Effective: next footnote.

Default: 0.

Register: \n[FPS]

Defines the footnote point size. If the value is larger than or equal to 1000, divide it by 1000 to get a fractional point size.

Effective: next footnote.

Default: \n[PS] - 2.

Register: \n[FVS]

Defines the footnote vertical spacing. If the value is larger than or equal to 1000, divide it by 1000 to get a fractional point size.

Effective: next footnote.

Default: \n[FPS] + 2.

Register: \n[FPD]

Defines the footnote paragraph spacing.

Effective: next footnote.

Default: \n[PD] / 2.

Miscellaneous Number Registers

Register: \n[MINGW]

Defines the minimum width between columns in a multi-column document.

Effective: next page.

Default: 2n.

Register: \n[DD]

Sets the vertical spacing before and after a display, a tbl table, an eqn equation, or a pic image.

Effective: next paragraph.

Default: 0.5v.